Fixnzip� Isn�T Your Normal Zipper Repair Kit. It�S A Replacement Zipper Slider That Requires No Tools And No Sewing To Install. Works Great For Wetsuits! Zippers Fail For A Variety Of Reasons. If The Teeth Separate After Being Zipped Up, Then The Zipper Slider Slider Is Probably Worn Out And Needs To Be Replaced. If The Zipper Is Pulled On Too Hard, It Can Come Off Track And No Longer Align The Teeth Properly. Sometimes The Slider Comes Off All Together. In Each Of These Scenarios, The Fixnzip Replacement Slider Will Take Care Of The Problem.