PolyBrakes from Winwood Technologies of Denver, Colo uses a polyurethane brake pad molded around an internal aluminum structure. The PolyBrake pad is 54mm by 13.8mm with a rim contact area of 48.5mm by 10mm. The contact area has a slight arch to mimic the shape of the rim. The polyurethane used is clear with a grey tint. The polyurethane plastic, when new, has a slight slipperiness. The beam and paddle that the polyurethane is molded around are clearly visible showing a 1/10" thick aluminum plate with 12 holes that the pad is molded around.
The PolyBrakes are made only in a non-threaded cantilever mounting bolt and sold only in pairs. The Silver aluminum mounting post is 6.95mm in diameter and has useful length of 23mm. The PolyBrake pads tested to an A/93 harness, the pair weight is 30 grams. $ Price in Catalog