The Drive Medical Walker Rear Tennis Ball Glides with Replacement Pads provide a quiet, smooth and durable glide experience when used with a walker. The Tennis Ball Glides last longer than plastic glide caps and are easy and safe to install. Comes complete with 1 additional pair of replacement glides pads. Easy and safe to install|Lasts longer than plastic glide cap|Provides a quiet, smooth, and durable glide experience when used with a walker|Patent Pending