Placed in a horse’s mouth, a snaffle bit is a type of reining device that was gentler for the horse, and allowed greater control and maneuverability (like in battle) for the rider over other types of bits. The bit here features a chain, which would have been strapped beneath the horse’s chin, as well as hooks, where the reins were attached.
Note that the pear-shaped pieces of the mouthpiece of the bit are tinned to reduce corrosion caused by exposure to horse saliva. This bit has ornamentation etched with acid and filled with silver. With these older pieces, the silver has largely eroded, but there are still some traces visible.