The Fix N' Zip is a zipper slider replacement that repairs zippers without tools or sewing. It has a patented spring plate design that enables it to fit over a range of sizes; teeth or coil, metal or plastic, fixing zippers on jackets, bags, tents, clothing, car covers, wet suits, shoes, sleeping bags, jeep windows, etc. It can even realign broken zipper teeth. It supports sustainability in that it encourages reuse of products and is, itself, reusable. All parts are designed and manufactured in the USA. Easy to install, it can fix most items with zippers in minutes. To find your zipper size: Most zippers have a size number (1-10) embossed on the back of the slider. / Small Zipper Slider: Teeth and amp; Coil Sizes 1-4 / Medium Zipper Slider: Teeth and amp; Coil Sizes 5-7 / Large Zipper Slider: Teeth and amp; Coil Sizes 8-10