{"product_id":"imscrews-5-16-18-x-4-carriage-bolts-304-stainless-steel-18-8-full-thread-structural-fasteners-for-4x4-posts-decks-heavy-timber-10-pcs","title":"IMSCREWS 5\/16-18 x 4 Carriage Bolts, 304 Stainless Steel (18-8), Full Thread Structural Fasteners for 4x4 Posts, Decks \u0026 Heavy Timber, 10 PCS","description":"\u003cp\u003e\u003cstrong\u003eIMSCREWS 5\/16\"-18 x 4\" Heavy-Duty 304 Stainless Steel Carriage Bolts (10 PCS)\u003c\/strong\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eSubstantial Reach for 4x4 Post and Structural Timber Connections\u003c\/strong\u003e\u003cbr\u003eThe IMSCREWS 5\/16\" x 4\" carriage bolt is engineered for structural projects requiring reliable penetration through thick materials. With a robust 5\/16-inch diameter and an extended 4-inch length, these bolts are the \u003cstrong\u003eideal\u003c\/strong\u003e choice for securing standard 4x4 timber posts (actual 3.5\"). They provide the necessary length to fully cross the post while leaving sufficient thread to accommodate heavy-duty washers and nuts for a \u003cstrong\u003esnug\u003c\/strong\u003e, permanent connection. Built for durability, they offer the structural stability required for outdoor pergolas, deck framing, and heavy timber construction.\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eHigh Durability and Safety-Focused Design\u003c\/strong\u003e\u003cbr\u003eForged from premium 18-8 (304) stainless steel, these fasteners are highly resistant to rust and corrosion in coastal or humid environments. The smooth round head offers a \u003cstrong\u003eclean\u003c\/strong\u003e, low-profile appearance that reduces snagging hazards, making them a safe choice for high-traffic residential areas and play equipment. The integrated square neck prevents the bolt from spinning during installation, allowing for easy, one-sided fastening with a single wrench from the nut side.\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003eSpecifications:\u003c\/strong\u003e\u003cbr\u003e- Thread Size: 5\/16\"-18 Coarse (UNC); Length: 4\" (Measured from Under Head)\u003cbr\u003e- Material: 304 (18-8) Stainless Steel; Full Thread\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003ePro-Tips:\u003c\/strong\u003e\u003cbr\u003e1. Use a 5\/16\" drill bit to ensure a \u003cstrong\u003esnug\u003c\/strong\u003e, structural fit for the square neck.\u003cbr\u003e2. Pair with stainless steel flat washers and hex nuts on the nut side to distribute load and protect wood fibers.\u003c\/p\u003e\u003ch3\u003eKey Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eExtended 4-Inch Reach: Specifically engineered to fully penetrate standard 4x4 posts (3.5 actual thickness) or join thick multi-layer beams with space for washers and nuts.\u003c\/li\u003e\n\u003cli\u003eHeavy-Duty 5\/16 Diameter: The robust 5\/16-inch shank offers superior shear resistance and load-bearing capacity compared to 1\/4 bolts, essential for structural outdoor joints.\u003c\/li\u003e\n\u003cli\u003ePremium 304 Stainless Steel: Forged from 18-8 (304) stainless steel for maximum rust protection in coastal air, humid gardens, and corrosive pressure-treated wood (ACQ).\u003c\/li\u003e\n\u003cli\u003eSafety Round Head Design: The smooth, drive-free domed head eliminates sharp protrusions, providing a snag-free finish that is safe for play sets, benches, and deck railings.\u003c\/li\u003e\n\u003cli\u003eAnti-Rotation Square Neck: The precision square shoulder locks firmly into wood fibers during installation, allowing for easy, one-sided tightening from the nut side.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eASIN:\u003c\/strong\u003e B0F2F68ZBG\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInternal SKU:\u003c\/strong\u003e IMS0818\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e 5\/16\"-18 x 4\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Stainless Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish:\u003c\/strong\u003e Stainless Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHead Style:\u003c\/strong\u003e Round\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Quantity:\u003c\/strong\u003e 10\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"IMSCREWS","offers":[{"title":"Default Title","offer_id":57034021273766,"sku":"B0F2F68ZBG","price":17.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0271\/2784\/0903\/files\/51ZaVl7AlSL_dc09caad-998e-4607-96c6-8652dbd62007.jpg?v=1787034838","url":"https:\/\/www.imscrews.com\/ru\/products\/imscrews-5-16-18-x-4-carriage-bolts-304-stainless-steel-18-8-full-thread-structural-fasteners-for-4x4-posts-decks-heavy-timber-10-pcs","provider":"IMSCREWS","version":"1.0","type":"link"}