The VPS501 is a parts kit that allows you to assemble your own goggles using different nosepieces and strap adjusters. Come with 3 different sized nosepieces, side clips, and a silicone strap the VPS501 is a kit designed for the VC511 corrective lenses (2 lenses required) or as a replacement parts kit for the V510 goggle. The kit can be easily adjusted with interchangeable side clips that are quick and easily released.