A huge variety of bits are available. Dressage bits and show jumping bits are both available. Bits come in 3 to 4 different sizes, ranging from 5″ to 6″. There are specialized bits that are used for special purposes. For example, gag bits are different than loose ring bits are different than Weymouth bits. Some bits accommodate 2 pairs of reins as well. Some bits replace parts of the bridle, for instance the Hackamore bit.