{"id":15466,"date":"2026-07-17T03:37:09","date_gmt":"2026-07-17T03:37:09","guid":{"rendered":"https:\/\/npt-lok.com\/?p=15466"},"modified":"2026-08-24T09:42:51","modified_gmt":"2026-08-24T09:42:51","slug":"tube-fittings-dimensions","status":"publish","type":"post","link":"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/","title":{"rendered":"How to Measure Tube Fitting Dimensions: Sizes, Thread Standards &#038; Size Chart"},"content":{"rendered":"<p><span style=\"font-weight: 400;\">Choosing the right fitting size is critical to keeping your system safe and leak-free. In this article, we discuss how to accurately measure <a href=\"https:\/\/npt-lok.com\/ja\/%e3%83%81%e3%83%a5%e3%83%bc%e3%83%96%e7%b6%99%e6%89%8b\/\">\u30c1\u30e5\u30fc\u30d6\u7d99\u624b<\/a> dimensions, choose the right size and avoid common sizing mistakes.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-11262\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2022\/08\/Tube-fittings.jpg\" alt=\"\u30c1\u30e5\u30fc\u30d6\u7d99\u624b\" width=\"498\" height=\"350\" \/><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_88 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u76ee\u6b21<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">\u30c8\u30b0\u30eb<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Measurement_Systems_Thread_Standards\" >Measurement Systems &amp; Thread Standards<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Measurement_Systems\" >Measurement Systems<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Thread_Standards\" >Thread Standards<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Tube_Fittings_Dimensions_Size_Chart\" >Tube Fittings Dimensions Size Chart<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#How_to_Measure_Tube_Fittings_Step-by-Step_Guide\" >How to Measure Tube Fittings: Step-by-Step Guide<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Tube_Fitting_Sizing_Mistakes_to_Avoid\" >Tube Fitting Sizing Mistakes to Avoid<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#FAQ\" >\u3088\u304f\u3042\u308b\u8cea\u554f<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/npt-lok.com\/ja\/tube-fittings-dimensions\/#Ready_to_Find_Your_Perfect_Size\" >Ready to Find Your Perfect Size?<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Measurement_Systems_Thread_Standards\"><\/span><span style=\"font-weight: 400;\">Measurement Systems &amp; Thread Standards<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">A fitting dimension generally consists of two parts: Size and Thread.<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Measurement_Systems\"><\/span><span style=\"font-weight: 400;\">Measurement Systems<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The most common mistake when determining fitting size is taking a direct caliper measurement and using that reading as the order size. In reality, there are three different sizing conventions based on the type of tubing.<\/span><\/p>\n<table>\n<tbody>\n<tr>\n<td><b>System<\/b><\/td>\n<td><b>Measurement Basis<\/b><\/td>\n<td><b>\u5fdc\u7528<\/b><\/td>\n<td><b>Example (1\/2&#8243; nominal)<\/b><\/td>\n<\/tr>\n<tr>\n<td><b>Tube (hard tubing)<\/b><\/td>\n<td><b>Actual Outside Diameter (OD)<\/b><\/td>\n<td><span style=\"font-weight: 400;\">Instrumentation tubing, double ferrule fittings<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Actual measured OD is exactly 1\/2&#8243; (12.7 mm)<\/span><\/td>\n<\/tr>\n<tr>\n<td><b>Hose<\/b><\/td>\n<td><b>Actual Inside Diameter (ID)<\/b><\/td>\n<td><span style=\"font-weight: 400;\">Hydraulic hose, rubber hose<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Actual measured ID is 1\/2&#8243;, OD is larger than 1\/2&#8243;<\/span><\/td>\n<\/tr>\n<tr>\n<td><b>Dash size<\/b><\/td>\n<td><b>Multiples of 1\/16&#8243;<\/b><\/td>\n<td><span style=\"font-weight: 400;\">Hydraulic fittings, high\u2011pressure systems<\/span><\/td>\n<td><span style=\"font-weight: 400;\">-8 equals 8\/16&#8243; (1\/2&#8243;). Refers to 1\/2&#8243; Hose I.D. for hydraulics, or 1\/2&#8243; Tube O.D. for instrumentation.<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3><span class=\"ez-toc-section\" id=\"Thread_Standards\"><\/span><span style=\"font-size: 24px; font-weight: 400;\">Thread Standards<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Once the size is determined, the correct thread standard must be matched.<\/span> <span style=\"font-weight: 400;\">Three main\u00a0 Thread standards are American, British, and Metric.<\/span><\/p>\n<p><b><a href=\"https:\/\/npt-lok.com\/ja\/%e8%a8%88%e8%a3%85%e7%94%a8%e3%83%91%e3%82%a4%e3%83%97%e7%b6%99%e6%89%8b\/npt%e7%b6%99%e6%89%8b\/\">\u6838\u4e0d\u62e1\u6563\u6761\u7d04<\/a> (National Pipe Tapered)<\/b><\/p>\n<p><span style=\"font-weight: 400;\">Characteristics: 60\u00b0 thread angle, 1:16 taper.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Sealing principle: Seals by metal\u2011to\u2011metal deformation of the tapered threads. In practice, PTFE tape or sealant is typically applied as an additional safeguard to ensure a reliable seal.<\/span><\/p>\n<p><b>BSP (British Standard Pipe)\u00a0<\/b><\/p>\n<p><span style=\"font-weight: 400;\">British threads have a 55\u00b0 thread angle. You must strictly distinguish between the following two subtypes, which are completely non\u2011interchangeable.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">BSPT (Tapered)<\/span><span style=\"font-weight: 400;\"><br \/>\n<\/span><span style=\"font-weight: 400;\">Tapered thread (similar concept to NPT, but different thread angle). Seals by mechanical wedging of the thread flanks.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">BSPP (Parallel)<\/span><span style=\"font-weight: 400;\"><br \/>\n<\/span><span style=\"font-weight: 400;\">Straight (parallel) thread with no taper. It cannot seal on the threads alone; it requires an O\u2011ring at the thread root, or a bonded seal (ED ring) on the flange face, to achieve a pressure\u2011tight joint.<\/span><\/li>\n<\/ul>\n<p><strong>Metric Threads<\/strong><\/p>\n<p><span style=\"font-weight: 400;\">Characteristics: 60\u00b0 thread angle, parallel straight threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Pitch is measured in millimeters (mm).\u00a0<\/span><\/p>\n<p><strong>UN\/UNF (Unified National Fine) Threads<\/strong><\/p>\n<p><span style=\"font-weight: 400;\">Characteristics: 60\u00b0 thread angle, parallel straight threads.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Application: Extremely common in hydraulic systems, especially on 37\u00b0 JIC and 45\u00b0 SAE flare fittings.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tube_Fittings_Dimensions_Size_Chart\"><\/span><span style=\"font-weight: 400;\">Tube Fittings Dimensions Size Chart<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Below is a quick reference for our commonly used sizes.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Our catalog uses the following standard abbreviations for fitting dimensions:<\/span><\/p>\n<p><span style=\"font-weight: 400;\">L = Overall length of the fitting<\/span><\/p>\n<p><span style=\"font-weight: 400;\">B = Effective thread length<\/span><\/p>\n<p><span style=\"font-weight: 400;\">C = Hex width across flats (nut size)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">D = Front ferrule outside diameter<\/span><\/p>\n<p><span style=\"font-weight: 400;\">F = Nut outside diameter \/ back ferrule length<\/span><\/p>\n<p><span style=\"font-weight: 400;\">E = Tube insertion depth<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-15470\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/double-ferrule-unions-size-.png\" alt=\"eg. double ferrule unions dimension\" width=\"505\" height=\"649\" srcset=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/double-ferrule-unions-size-.png 505w, https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/double-ferrule-unions-size--9x12.png 9w\" sizes=\"auto, (max-width: 505px) 100vw, 505px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Note: Only standard sizes are listed above. For complete sizes, you can skip to the download section at the bottom.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_Measure_Tube_Fittings_Step-by-Step_Guide\"><\/span><span style=\"font-weight: 400;\">How to Measure Tube Fittings: Step-by-Step Guide<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Step 1: Identify the Connection Type<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Before measuring, observe the connection style. Tube connection (ferrule bite) \/ hose connection (barb or crimp) \/ threaded connection?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If it is a threaded fitting, observe the diameter along the length of the threads to determine whether they are parallel or tapered.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For male threads, if the diameter is smaller at the tip and larger at the base, it is a tapered thread (e.g., NPT, BSPT).<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For female threads, this taper is internal, making it difficult to distinguish with the naked eye. Therefore, you need to use calipers to measure the inner diameter at both the opening and the deepest point of the thread to verify that the measurements are consistent.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Step 2: Measure Physical Diameters<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Use a caliper to measure the dimensions of the fitting.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For tube fittings: measure the outside diameter (OD) of the mating tube.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For male threads: measure the outer diameter (OD) across the widest point of the thread.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For female threads: insert the caliper and measure the inner diameter (ID) at the widest point inside the thread.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Step 3: Determine Thread Type, Pitch, and Standards<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Note: Do not order a pipe thread fitting based on the direct caliper measurement alone.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">With your caliper measurements from Step 2, you now need to identify the thread profile:<\/span><\/p>\n<ol>\n<li><span style=\"font-weight: 400;\">Check for Thread Tapered or Parallel<\/span><\/li>\n<\/ol>\n<p><span style=\"font-weight: 400;\">Tapered\u2192NPT (60\u00b0 thread angle), BSPT (55\u00b0 thread angle)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Parallel\u2192BSPP (55\u00b0), Metric (60\u00b0), and UN\/UNF (60\u00b0 \u2014 widely used on JIC and SAE flare fittings)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">2. Count the Threads with a Thread Pitch Gauge.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Step 4: Determine the Thread Standard and match with charts<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Combine the diameter measurement from Step 2 with the thread density in Step 3, then compare against the fitting size charts to identify the standard.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For example, if a male thread measures 20.9 mm in outer diameter and has 14 threads per inch, the thread is likely 1\/2&#8243; NPT or 1\/2&#8243; BSP. Make the final determination by checking the thread angle and taper.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Tube_Fitting_Sizing_Mistakes_to_Avoid\"><\/span><span style=\"font-weight: 400;\">Tube Fitting Sizing Mistakes to Avoid<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Interchanging NPT and BSP Threads<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">NPT and BSPT are both tapered threads,\u00a0 NPT has a 60\u00b0 thread angle while BSPT has a 55\u00b0 angle. Forcing them together will cause mismatched threads to gall and seize locally. This not only fails to seal but can permanently damage the port. Under high pressure, it poses a high risk of blowout and leakage.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Mixing Metric and Fractional (Inch) Fittings<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Metric and inch sizes are visually very close\u2014for example, 1\/4&#8243; OD is actually 6.35 mm, making it extremely difficult to distinguish from 6 mm. If a 6 mm tube is forced into a 1\/4&#8243; ferrule fitting, the ferrule cannot grip the tube uniformly. Upon system pressurization, the tube may be blown out, causing a serious fluid accident.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Misusing 37\u00b0 JIC and 45\u00b0 SAE Flare Fittings<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">In smaller dash sizes such as -4 and -8, JIC and SAE flare fittings share identical thread specifications, leading many to believe they are interchangeable. They are not. The seal depends on the mating of the flare angles (37\u00b0 to 37\u00b0, or 45\u00b0 to 45\u00b0). Mixing them results in incomplete contact between the sealing surfaces, and high\u2011pressure media will spray out through the gap.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"FAQ\"><\/span><span style=\"font-weight: 400;\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Q1: Can I use NPT fittings with BSPP ports?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">No, they can not be connected directly. You must use a <a href=\"https:\/\/npt-lok.com\/ja\/%e8%a8%88%e8%a3%85%e7%94%a8%e3%83%91%e3%82%a4%e3%83%97%e7%b6%99%e6%89%8b\/bspp-to-npt-adapter\/\">thread adapter<\/a> (convertor) to transition between NPT (tapered) and BSPP (parallel) threads safely.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q2: What is the difference between Tube and Pipe in sizing?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Pipes are measured by their approximate inside diameter (Nominal Pipe Size), while tubes are measured by their exact outside diameter<\/span><span style=\"font-weight: 400;\">.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Q3: What does dash size -6 mean in tube fittings?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dash size is based on 1\/16&#8243; increments. Therefore, -6 represents 6\/16&#8243; which equals 3\/8&#8243;.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Ready_to_Find_Your_Perfect_Size\"><\/span><span style=\"font-weight: 400;\">Ready to Find Your Perfect Size?<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400;\">We offer a comprehensive range of dimensions to meet your specific system requirements.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Our Most Common Sizes include:<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Fractional (Inch) OD: 1\/8&#8243;, 1\/4&#8243;, 3\/8&#8243;, 1\/2&#8243;, 1&#8243;<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Metric OD: 3mm, 6mm, 10mm, 12mm, and more.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Need a different size or full technical specifications?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Download our complete <a href=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2026\/07\/Tube-fittings.pdf\">\u30c1\u30e5\u30fc\u30d6\u7d99\u624b\u30ab\u30bf\u30ed\u30b0<\/a> to find the exact dimensions, pressure ratings, and material options tailored to your application. Learn more <a href=\"https:\/\/npt-lok.com\/ja\/%e7%a7%81%e3%81%9f%e3%81%a1%e3%81%ab%e3%81%a4%e3%81%84%e3%81%a6\/\">\u79c1\u305f\u3061\u306b\u3064\u3044\u3066<\/a>.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-12847 aligncenter\" src=\"https:\/\/npt-lok.com\/wp-content\/uploads\/2023\/08\/brand.jpg\" alt=\"tube fittings brand\" width=\"100\" height=\"100\" \/><\/p>","protected":false},"excerpt":{"rendered":"<p>Choosing the right fitting size is critical to keeping your system safe and leak-free. In this article, we discuss how to accurately measure tube fitting dimensions, choose the right size and avoid common sizing mistakes. Measurement Systems &amp; Thread Standards A fitting dimension generally consists of two parts: Size and Thread. Measurement Systems The most [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-15466","post","type-post","status-publish","format-standard","hentry","category-blog"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How to Measure Tube Fitting Dimensions: Sizes, Thread Standards &amp; Size Chart<\/title>\n<meta name=\"description\" content=\"Need accurate tube measurement? 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