This is a "revolvable cane" which is a replacement of the cane tip (that rubbery grey piece attached to the bottom of the cane) will allow easier stability for people using canes and crutches while walking on unstable levels, like bumps, stairs, hills. and etc.

The default file currently fits 1 inch canes and crutches and in order to fit it, you need to know your diameter size and divide it by one. Example your cane size ÷ 1 inch