ERS Centaur Blue Steel Double Joint Disk BoucherOur Blue Steel bits are made of a technologically advanced version of Black Steel (traditional Sweet Iron). Blue Steel oxidizes faster and easier compared to Black Steel. It will rust when in contact with air and humidity. This surface rust tastes sweet and naturally stimulates additional saliva production, encouraging better acceptance of the bit by the horse. Brass Roller Discs provide an additional comfort to certain horses by giving them something