JMP Aluminum Racing chain wheels If you attach importance to low weight, quality and design, you will hardly find better chainrings. The JMP aluminum racing chain wheels are made from 7075 T6 aluminum, which is mainly used in aviation. This aluminum alloy is characterized by enormous strength, tightness and low weight. Milling in the tooth base of the sprocket guarantee optimum self-cleaning. These millings ensure that the dirt can not settle between the teeth and thereby do not wear the chain and sprocket as quickly as normal aluminum chain wheels. Apart from the "protective effect", the sprocket is not only more durable, but also looks more top-quality. - high performance - unique quality - high quality - light weight