Adjustable Hunt Breastplate
Being the classic breastplate for English riding, the hunting breastplate is the most common type. It consists of a yoke (with a neck and wither strap), a breast strap at the bottom of the yoke which runs through the horse's front legs and attaches to the girth, and two straps at the top of the yoke which attach to the D-rings of a saddle. There are usually buckles for adjusting the size of the yoke as well as the length of the straps which attach to the saddle and girth. The hunting breastplate not only helps to prevent the saddle from slipping, but also may be used to attach standing and running martingales, which are clipped or buckled onto a ring at the chest.
The hunting breastplate is most commonly made of leather, and some have elastic inserts on the yoke to help prevent it from restricting the horse's shoulders. Those used in endurance riding are commonly made of lightweight nylon or another synthetic material.
The hunting breastplate is worn by endurance horses, show hunters, fox hunters, equitation horses, eventers (it can be seen used in all three phases), and show jumpers. It is also occasionally see in flat racing, as well as steeplechase.