{"product_id":"trek-water-bottle-nutsert-plug-m4-x-13mm-black-thread-protector-for-unused-bottle-cage-mounts","title":"Trek Water Bottle Nutsert Plug M4 x 13mm Black – Thread Protector for Unused Bottle Cage Mounts","description":"\u003cp\u003eThe \u003cstrong\u003eTrek Water Bottle Nutsert Plug M4 x 13mm\u003c\/strong\u003e is a genuine Trek spare part that fills and protects unused bottle cage mounting threads on Trek frames. Trek frames typically include multiple bottle cage mount positions — on the down tube, seat tube, and sometimes the fork — and any mount not in use is left with an exposed threaded nutsert that can collect dirt, mud, and moisture over time. This plug threads into the M4 x 13mm nutsert to seal the opening, protecting the threads from corrosion and contamination and giving the frame a clean, finished appearance without exposed hardware.\u003c\/p\u003e\n\n\u003cp\u003eA small but practical detail — particularly relevant for riders who use only one bottle cage position, run a frame bag that covers a mount, or have removed a cage for a specific build. The plug is black to blend with most Trek frame colourways and is straightforward to install with a 3mm hex key. Sold individually. Browse our full \u003ca href=\"\/collections\/bottles-cages\"\u003ebottles and cages collection\u003c\/a\u003e for bottle cages, bottles, and accessories.\u003c\/p\u003e\n\n\u003ch3\u003eWhat It's Good For\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eProtecting unused M4 x 13mm bottle cage mount threads on Trek frames\u003c\/li\u003e\n\u003cli\u003ePreventing dirt, mud, and moisture ingress into exposed nutserts\u003c\/li\u003e\n\u003cli\u003eClean, finished appearance on unused mount positions\u003c\/li\u003e\n\u003cli\u003eGenuine Trek spare part — correct fit for Trek frame nutserts\u003c\/li\u003e\n\u003cli\u003eSimple installation with a 3mm hex key\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat It's NOT Good For\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eNon-M4 bottle cage mounts — check your frame's thread specification before purchasing\u003c\/li\u003e\n\u003cli\u003eNon-Trek frames where nutsert dimensions may differ\u003c\/li\u003e\n\u003cli\u003eReplacing a bottle cage — this is a thread protector plug only\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eHow do I know if my Trek frame uses M4 x 13mm nutserts?\u003c\/strong\u003e\u003cbr\u003eMost Trek road, gravel, and MTB frames from recent years use M4 nutserts for bottle cage mounts. If you're unsure, check your frame's specification on the Trek website using your frame's model and year, or measure the thread diameter of the existing mount. M4 refers to a 4mm thread diameter.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eDo I need a tool to install it?\u003c\/strong\u003e\u003cbr\u003eYes — the plug is installed with a 3mm hex key (Allen key), the same tool used to install most bottle cage bolts. Thread it in finger-tight first, then snug with the hex key — do not overtighten as the nutsert is aluminium and can be damaged by excessive torque.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eIs this sold as a single plug or a pack?\u003c\/strong\u003e\u003cbr\u003eThis listing is for a single plug. If you have multiple unused mount positions to fill, you'll need to add the appropriate quantity to your order.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWill it fit non-Trek frames?\u003c\/strong\u003e\u003cbr\u003eThe plug is designed for Trek's M4 x 13mm nutserts. Many other brands also use M4 bottle cage mounts, so it may fit — but thread depth and nutsert dimensions can vary between manufacturers. If in doubt, check your frame's specification or contact us before purchasing.\u003c\/p\u003e","brand":"Trek","offers":[{"title":"Default Title","offer_id":45471683346607,"sku":"W308963","price":0.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0654\/2003\/4223\/files\/1707813466-24603500.jpg?v=1768512623","url":"https:\/\/www.swinnertoncycles.co.uk\/products\/trek-water-bottle-nutsert-plug-m4-x-13mm-black-thread-protector-for-unused-bottle-cage-mounts","provider":"Swinnerton Cycles","version":"1.0","type":"link"}