These premium Endless wheels are made in the US with a high performance urethane formula that delivers an enhanced experience balancing speed, wear, grip, and sliding performance. The 68mm wheel was specifically developed for Endless Arc CS 5-wheel frames, which require 4x68mm wheels. It offers incredible grip when on deep edges which makes it excellent for 5-wheel wizard skating and slalom skating. The relatively large core increases overall wheel stiffness and speed.