BikeMaster starts with high pressure aluminum die-casting to make a strong, stable, corrosion resistant shoe. The friction material is chosen for a balance of performance and longevity for the application. Then it is bonded to the brake shoe casting, using a high temperature process. In order to insure that the shoe has a perfect radius, the face of the friction material is machined to make sure it is a perfect fit to the brake drum. Then, to make sure that brake application is smooth, not grabby, they chamfer the edges of the shoes, and give the material a extra chamfer on the leading and trailing edges of the friction material. Brake shoes are designed to be a direct replacement for O.E.M. shoes, and meet or exceed the O.E.M. performance. Comes complete with new springs. NO asbestos is used. Note: Some applications will require two sets of shoes; check your manual.