Snap-on nylon glide caps reduces floor maintenance issues such as rusting from traditional glides or scratching and snagging of carpet or hard floors. The nylon surface of the glide cap limits friction on your floors and therefore reduces floor scratching eliminates rust spots and reduces noise. Easily snaps onto an existing glide base. Perfect for use on cafeteria seating classroom chairs desks and event seating and difficult for students to remove. Choose a cap size to fit snug on your furniture by measuring the base of your existing glide. Note: The given diameter size is for the glide base (or flange) diameter to be fitted. Glide cap will be slightly wider at the bottom and midsection interior of the glide cap than at the top so that the glide cap will "snap" onto (i.e. it will fit over and around and not into) the glide base (or flange). If you are interested in trying to use these glide caps as inserts the outside diameter is approximately 1-7/32" with an approximate height of 3/8".