Indeed, the Tom Thumb bit is a snaffle bit for the western horse. Snaffles are mouthpieces used to control horses. A snaffle bit, as its name suggests, is a bit that has two prongs, one at each end, which are joined by a joint. The joint is either a metal or plastic cap. The Tom Thumb bit is considered an advanced bit because it requires a lot of training and practice to be able to use it effectively. The Tom Thumb bit is made up of a long metal or plastic shank with two prongs, or tips, at the end. There is also a joint in the middle where the prongs join. The mouthpiece of the Tom Thumb bit is very similar to the mouthpiece of a snaffle bit.