{"product_id":"8020-5-16-18-x-687-flanged-button-head-socket-cap-screw","title":"80\/20 Flanged Button Head Socket Cap Screw - 5\/16-18 x .687\" (P\/N 3330)","description":"\u003cp\u003e\u003cstrong\u003eThe bolt that goes with the T-nut. Zinc-plated, flanged button head, 5\/16-18 × .687\" — 80\/20 part number 3330.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe flange is the point. A flanged button head spreads its clamping load across a wider area than a plain button head, which stops the bolt from pulling through a bracket hole and stops the head from digging into soft aluminum as you torque it.\u003c\/p\u003e\n\u003cp\u003eThe .687\" length is matched to a standard bracket thickness plus a T-nut in a 15 series slot. Longer bolts bottom out inside the slot before they clamp; shorter ones do not get enough thread engagement. This is the one that is right.\u003c\/p\u003e\n\u003ch2\u003eWhat it is for\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eBolting brackets, plates and accessories to 15 series 80\/20 extrusion, paired with a 5\/16-18 T-nut.\u003c\/li\u003e\n\u003cli\u003eAnywhere a plain button head would dig into or pull through the bracket.\u003c\/li\u003e\n\u003cli\u003eInterior framing and protected locations — for exposed exterior use, consider the black stainless version.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eCompatibility\u003c\/h2\u003e\n\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eExtrusion\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e15 series 80\/20 and equivalent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eThread\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5\/16-18\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLength\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e.687\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePairs with\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5\/16-18 T-nuts, standard or double\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3330\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cp\u003eThe 15 series is the 1.5 inch profile — the size almost every van roof rack and interior framing system is built from. If your extrusion measures 1.5 in across the face and takes a 5\/16-18 fastener, this is your hardware.\u003c\/p\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eHead\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eFlanged button head socket cap\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFinish\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eZinc\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eThread\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5\/16-18\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLength\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e.687\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDrive\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eHex socket\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3330\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch2\u003eWhat's included\u003c\/h2\u003e\n\u003cul\u003e\u003cli\u003e(1) 5\/16-18 × .687\" zinc flanged button head socket cap screw\u003c\/li\u003e\u003c\/ul\u003e\n\u003ch2\u003eWorking with it\u003c\/h2\u003e\n\u003cp\u003eA quality hex key that actually fills the socket is worth more than any other tool on a rack build. Rounded-out sockets on a roof rack, three years and one winter later, are the reason people cut brackets off with an angle grinder.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eUse a properly fitting hex key or bit — a sloppy one rounds the socket.\u003c\/li\u003e\n\u003cli\u003eDo not overtighten. You are clamping into an aluminum slot, and there is a point past which more torque only deforms the extrusion.\u003c\/li\u003e\n\u003cli\u003eRe-check torque after the first long drive. Vibration finds every fastener.\u003c\/li\u003e\n\u003cli\u003eFor exterior use in a salted climate, the black stainless equivalent (3607) has better corrosion life.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eQuestions we get asked\u003c\/h2\u003e\n\u003ch3\u003eHow do I know if my extrusion is 15 series?\u003c\/h3\u003e\n\u003cp\u003eMeasure across the flat face of the profile. A 15 series extrusion is 1.5 in wide (or a multiple — 1.5 × 3.0, and so on) and the T-slot takes a 5\/16-18 fastener. If your rack came from Unaka, 80\/20 Inc., or most van rack makers in North America, it is 15 series.\u003c\/p\u003e\n\u003ch3\u003eHow many should I order?\u003c\/h3\u003e\n\u003cp\u003eCount your joints, then add 20%. Rack hardware is the cheapest thing in a build and the most annoying thing to run out of halfway through a Saturday. We have never once regretted having spare T-nuts in the drawer.\u003c\/p\u003e\n\u003ch3\u003eWhy .687\" and not a rounder number?\u003c\/h3\u003e\n\u003cp\u003eBecause it is matched to the geometry of the 15 series slot plus a standard bracket. It is long enough for full thread engagement into a T-nut and short enough not to bottom out inside the slot.\u003c\/p\u003e\n\u003ch3\u003eZinc or stainless?\u003c\/h3\u003e\n\u003cp\u003eZinc is fine indoors and under a rack fairing. If the bolt head sits exposed on a roof rack through a salted winter, spend the extra on the black stainless version.\u003c\/p\u003e\n\u003ch2\u003ePairs well with\u003c\/h2\u003e\n\u003cul\u003e\u003cli\u003e\u003ca href=\"\/collections\/van-life-parts\"\u003eVan roof rack, ladder and 80\/20 hardware\u003c\/a\u003e\u003c\/li\u003e\u003c\/ul\u003e\n\u003cp\u003eSold and shipped by Campervan Parts R Us, the parts counter of Noke Van Co. — a working van conversion shop in Roanoke, Virginia. If you are unsure whether this fits your van, email us the year, model and wheelbase and we will check it against a build sheet before you order.\u003c\/p\u003e","brand":"Unaka Gear Co.","offers":[{"title":"Default Title","offer_id":51849985130781,"sku":"3330","price":0.53,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0704\/5831\/0941\/files\/8020-5-16-18-x-687-flanged-button-head-socket-cap-screw-3330-30602973053092.png?v=1780690577","url":"https:\/\/campervanpartsrus.com\/products\/8020-5-16-18-x-687-flanged-button-head-socket-cap-screw","provider":"Noke Van Co","version":"1.0","type":"link"}