{"product_id":"m4-x-12mm-brass-round-head-phillips-screws-gbt818","title":"Solid Brass M4 x 12mm Round Head Phillips Machine Screws – GB\/T818, Fully Threaded","description":"\u003cstyle\u003e\n  \/* 统一前缀 hdiy-，避免样式冲突 *\/\n  .hdiy-product-wrap {\n    margin: 0;\n    padding: 0;\n  }\n  .hdiy-product-wrap h2,\n  .hdiy-product-wrap h3 {\n    margin-top: 1.5em;\n    margin-bottom: 0.5em;\n    font-weight: 600;\n  }\n  .hdiy-product-wrap p {\n    margin-bottom: 1em;\n    line-height: 1.5;\n  }\n  .hdiy-features-list {\n    list-style: none;\n    padding-left: 0;\n  }\n  .hdiy-features-list li {\n    margin-bottom: 0.75em;\n    padding-left: 1.5em;\n    position: relative;\n    line-height: 1.4;\n  }\n  .hdiy-features-list li::before {\n    content: \" \";\n    position: absolute;\n    left: 0;\n    top: 0;\n  }\n  .hdiy-table-wrapper {\n    overflow-x: auto;\n    margin: 1.2em 0;\n  }\n  .hdiy-specs-table {\n    width: 100%;\n    border-collapse: collapse;\n    font-size: 0.95rem;\n    background: #fff;\n  }\n  .hdiy-specs-table th,\n  .hdiy-specs-table td {\n    border: 1px solid #ddd;\n    padding: 10px 12px;\n    text-align: left;\n    vertical-align: top;\n  }\n  .hdiy-specs-table th {\n    background-color: #f5f5f5;\n    font-weight: 600;\n    width: 35%;\n  }\n  .hdiy-faq-item {\n    margin-bottom: 1.25rem;\n    border-bottom: 1px solid #eee;\n    padding-bottom: 0.75rem;\n  }\n  .hdiy-faq-question {\n    font-weight: 700;\n    margin-bottom: 0.35rem;\n    font-size: 1rem;\n  }\n  .hdiy-faq-answer {\n    margin-top: 0;\n    line-height: 1.45;\n    color: #2c2c2c;\n  }\n  @media (max-width: 640px) {\n    .hdiy-specs-table th,\n    .hdiy-specs-table td {\n      padding: 8px 10px;\n    }\n  }\n\u003c\/style\u003e\n\u003cdiv class=\"hdiy-product-wrap\"\u003e\n\u003c!-- 产品概述 --\u003e\n\u003ch2\u003e🟡 Product Overview: Solid Brass M4 x 12mm Round Head Phillips Screws – GB\/T818\u003c\/h2\u003e\n\u003cp\u003eWhether you're restoring a vintage radio, building a marine instrument, or just need a non‑magnetic, corrosion‑resistant fastener, these solid brass round head Phillips machine screws are a perfect fit. This listing is for M4 diameter, 12mm length – a common size for electronics enclosures, furniture hardware, and decorative trim. Manufactured by BRT Fasteners to GB\/T818 standards, each screw has a protective oil coating to prevent tarnish during storage. The round (pan) head gives a clean, low‑profile finish, and the Phillips drive works with standard #1 or #2 bits. Length is measured under the head, so an M4 x 12mm screw has 12mm of threaded shank below the rounded top. Fully threaded with coarse pitch (M4x0.7), these brass screws are reliable, attractive, and ready to ship in plastic packaging.\u003c\/p\u003e\n\u003c!-- 产品特点列表 --\u003e\n\u003ch2\u003e✨ Why These Brass Round Head Phillips Screws Stand Out\u003c\/h2\u003e\n\u003cul class=\"hdiy-features-list\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eSolid brass construction\u003c\/strong\u003e – Naturally corrosion‑resistant, non‑magnetic, and non‑sparking. Perfect for electrical applications, boat hardware, and antique restoration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRound (pan) head design\u003c\/strong\u003e – Low‑profile rounded head with a flat bearing surface. Sits neatly on surfaces and gives a classic, finished look.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePhillips drive\u003c\/strong\u003e – Works with standard #1 or #2 Phillips screwdrivers. Easy to install with common tools.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGB\/T818 standard\u003c\/strong\u003e – Precision head dimensions (dk = 6.5mm, k = 2.2mm for M4) and consistent thread geometry.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully threaded, M4 coarse pitch (0.7mm)\u003c\/strong\u003e – Threads run the entire shank length, providing maximum grip in thin materials.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtective oil coating\u003c\/strong\u003e – A light oil film prevents tarnish during storage and handling. Wipe before use if desired.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlastic packaging\u003c\/strong\u003e – Keeps screws organized and protected for shipping.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- 规格参数表格（主要针对M4 x 12mm，附带尺寸参考） --\u003e\n\u003ch2\u003e📏 Technical Specifications – M4 x 12mm Brass Round Head Screws (GB\/T818)\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-table-wrapper\"\u003e\n\u003ctable class=\"hdiy-specs-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003cth\u003eDetails\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eBRT Fasteners\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eProduct Type\u003c\/th\u003e\n\u003ctd\u003eSolid Brass Round Head Phillips Machine Screws\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eStandard\u003c\/th\u003e\n\u003ctd\u003eGB\/T818\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eBrass (solid, unplated)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSurface Treatment\u003c\/th\u003e\n\u003ctd\u003eProtective oils (light anti‑tarnish film)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eScrew Size\u003c\/th\u003e\n\u003ctd\u003eM4 (4mm thread diameter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eThread Pitch\u003c\/th\u003e\n\u003ctd\u003e0.7mm (standard metric coarse)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eThread Type\u003c\/th\u003e\n\u003ctd\u003eFully threaded\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eLength (under head)\u003c\/th\u003e\n\u003ctd\u003e12mm (example – other lengths available separately)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHead Diameter (dk)\u003c\/th\u003e\n\u003ctd\u003e6.5mm (per GB\/T818)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHead Height (k)\u003c\/th\u003e\n\u003ctd\u003e2.2mm (per GB\/T818)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePackaging\u003c\/th\u003e\n\u003ctd\u003ePlastic bag \/ plastic packaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c!-- 尺寸参考表（展示M2-M10常用规格，但不分散注意力） --\u003e\n\u003ch3\u003e📐 GB\/T818 Head Dimensions Reference (for other sizes)\u003c\/h3\u003e\n\u003cdiv class=\"hdiy-table-wrapper\"\u003e\n\u003ctable class=\"hdiy-specs-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eScrew Size (d)\u003c\/th\u003e\n\u003cth\u003eHead Diameter (dk)\u003c\/th\u003e\n\u003cth\u003eHead Height (k)\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eM2\u003c\/td\u003e\n\u003ctd\u003e3.1mm\u003c\/td\u003e\n\u003ctd\u003e1.1mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM2.5\u003c\/td\u003e\n\u003ctd\u003e4.1mm\u003c\/td\u003e\n\u003ctd\u003e1.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM3\u003c\/td\u003e\n\u003ctd\u003e5.0mm\u003c\/td\u003e\n\u003ctd\u003e1.7mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM3.5\u003c\/td\u003e\n\u003ctd\u003e5.5mm\u003c\/td\u003e\n\u003ctd\u003e2.0mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eM4\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e6.5mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003e2.2mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM5\u003c\/td\u003e\n\u003ctd\u003e8.4mm\u003c\/td\u003e\n\u003ctd\u003e2.9mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM6\u003c\/td\u003e\n\u003ctd\u003e9.8mm\u003c\/td\u003e\n\u003ctd\u003e3.4mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM8\u003c\/td\u003e\n\u003ctd\u003e13.0mm\u003c\/td\u003e\n\u003ctd\u003e4.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eM10\u003c\/td\u003e\n\u003ctd\u003e17.1mm\u003c\/td\u003e\n\u003ctd\u003e6.0mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c!-- 常见问题 FAQ --\u003e\n\u003ch2\u003e❓ FAQs – M4 Brass Round Head Phillips Screws\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 Are these screws fully threaded? How is length measured?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eYes – they are fully threaded from just under the head to the tip. Length is measured from the underside of the head (the flat bearing surface) to the tip, not including the round head. This M4 x 12mm screw has a 12mm threaded shank.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 Will brass screws rust or tarnish over time?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eBrass does not rust like steel. It may develop a darker patina or slight greenish tint (verdigris) over years in damp or salty environments. The protective oil coating delays tarnish during storage. For indoor use, they'll stay golden for a long time. For outdoor use, they outperform plain steel but aren't as corrosion‑resistant as stainless – ideal for decorative or low‑moisture exterior work.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 What Phillips screwdriver size works best for M4 brass screws?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eAn M4 round head Phillips screw typically uses a PH1 or PH2 bit. PH1 gives better engagement in brass without overtightening. Use a quality driver to avoid cam‑out.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 Can I use these screws with nuts, or are they self‑tapping?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eThese are machine screws – they require a matching M4 metric nut or a pre‑tapped hole. They are not self‑tapping. For best results, pair with brass or stainless steel M4 nuts.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 Are M4 brass screws magnetic? Will they interfere with electronics?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eBrass is completely non‑magnetic. That makes them perfect for sensitive electronic equipment, compass housings, or any application where stray magnetism is a problem.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-item\"\u003e\n\u003cdiv class=\"hdiy-faq-question\"\u003e🔸 Do you offer other lengths or sizes besides M4 x 12mm?\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq-answer\"\u003eYes – we stock other diameters (M2–M10) and lengths. Please check our store for additional listings or contact us for custom orders.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"HomeDIYer","offers":[{"title":"5","offer_id":52260020879634,"sku":"A3803-0","price":6.38,"currency_code":"USD","in_stock":true},{"title":"15","offer_id":52260020912402,"sku":"A3803-1","price":7.68,"currency_code":"USD","in_stock":true},{"title":"30","offer_id":52260020945170,"sku":"A3803-2","price":15.49,"currency_code":"USD","in_stock":true},{"title":"50","offer_id":52260020977938,"sku":"A3803-3","price":19.71,"currency_code":"USD","in_stock":true},{"title":"100","offer_id":52260021010706,"sku":"A3803-4","price":30.18,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Main-01_7abfb410-7012-4785-9ec8-d6b590d8fd96.jpg?v=1779086399","url":"https:\/\/homediyer.com\/products\/m4-x-12mm-brass-round-head-phillips-screws-gbt818","provider":"HomeDIYer","version":"1.0","type":"link"}