The Flexyfoot Replacement Foot has been designed to be used as a replacement when the Flexyfoot rubber ferrules \"foot\" is broken or worn.This replacement foot comes in one size and is able to fit all Flexyfoot ferrules. The new foot simply screws into any Flexyfoot collar; the part that is attached to your walking aid. It is available in either a black or grey tread from this area of the website. If greater shock absorbency is needed for full weight bearing or for active users, all replacement feet come with two O rings that can be fitted to the foot.