Breastplate (tack)

A breastplate (used interchangeably with breastcollar, breaststrap and breastgirth) is a piece of riding equipment used on horses. Its purpose is to keep the saddle or harness from sliding back.

On riding horses, it is most helpful on horses with large shoulders and a flat ribcage. It is also a safety feature, especially on cross-country, should a rider's girth or billets break, as she will have enough time to stop the horse and dismount before the saddle slipped off the animal's back or underneath its belly. The breastplate is used on both English and Western saddles. When used in English riding, the hunting breastplate is made of thinner straps of leather, as is the western style used for horse shows. Working western horses in disciplines that involve work with cattle use a thicker, sturdier style.

The breastcollar harness is one of two standard harness designs, the other being the collar and hames design. The breastcollar harness is used to pull light loads, such as at horse shows and for harness racing. It can only be used for lighter loads because it places the weight of the load on the sternum of the horse, which is not suitable for heavy pulling, plus it can put pressure on the windpipe and reduce a horse's air supply.

Being the classic breastplate for English riding, campdrafting or stockwork, the stockman's or 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 a Market Harborough or standing and running martingales, which are clipped or buckled onto a ring at the chest.

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