Features Super Strong Clear Polycarbonate Construction Waterproof and Shock Proof Available Colors: Red, Green, Red/Green Strobing Fits X, H, S, and GT Arrows H (white bushing) = Fits smaller diameter carbon .233 ID shafts GT (black bushing) = Fits smaller diameter carbon .246 ID shafts S (gray bushing) = Fits standard carbon .244 ID shafts X (no bushing) = Fits smaller diameter carbon .204 ID shafts Each nock in this package weighs approximately 25 grains Delivers more than 20 hours of lithium-powered battery life