The 6” Filter Replacement O-Ring Kit is for use with all 6” Hi-Flow, Dry-Sump and Screw-On See Through Filter Assemblies. This Kit consists of three O-Rings. The smallest of the three fits into the sight window (O-Ring # V-159). The larger O-Ring fits into the filter top housing (O-Ring # V-161) and the largest O-Ring fits into the window retainer (O-Ring # V-162). All O-Rings are made of Viton® which is heat, chemical and fuel resistant. Recommended to install new O-Rings into See Through Filter when replacing the sight window in all 6” filter assemblies.