Upgrade your Gen 7 Cat Exercise Wheel (sold separately) with these One Fast Cat Gen 7 Felt Outer Wheel Pads. Designed to fit perfectly along the exterior faces of your wheel’s center tracks, these pads will not only enhance the look but also the feel of your kitty’s exercise experience. Each set includes enough pads to cover the exterior of one Gen 7 wheel, and they are specifically made for exterior use only. These pads are not compatible as interior traction pads. Plus, they are easy to apply—simply peel off the paper backing and stick the adhesive side onto the plastic wheel.