Zippers are everywhere in our daily lives. YKK zipper is far superior to other zipper brands and will outlast non name brand zippers 10 to 1. These are not the cheap "plastic" sliders you see advertised in other auctions. Plastic sliders will not function long before failing due to the wear of the inside against the chain. Please note if you plan to replace only the sliders on your zipper, it is important to know the brand of the zipper. If it is made by "YKK" you can find "YKK" somewhere on the slider. If it does not have "YKK" it is another brand and my sliders may not work.