Crupper

A crupper (/ˈkrʌpər/; occ. spelled crouper) is a piece of tack used on horses and other equids to keep a saddle, harness or other equipment from sliding forward.

The crupper consists of a loop (the crupper itself) and an adjustable strap (crupper strap or back strap) that connects the crupper to back of a riding saddle or the other parts of a harness. The strap runs from the horse's dock, over the croup, to the saddle or to the back band (sometimes called the saddle) of a harness.

Usually made of leather, the crupper loop is stuffed, traditionally with linseed to keep it supple in use, and molded into a tube that is shaped into a loop. The crupper may be sewn to its strap, or attached to the strap by one or two buckles. If the crupper has no buckle, then the skirt of the horse's tail is folded up onto the tailbone and the tailbone is slipped through the crupper. If it has buckles, the crupper is unbuckled and passed under the dock.

A crupper is used to keep the equipment placed on a horse's back from slipping forward. Cruppers are seen most often on horse harnesses. They are also used on the surcingles of bitting rigs, riding saddles, and, occasionally, pack saddles.

A crupper needs to be snug enough to keep the saddle or harness in place, but not so tight that the horse is irritated or the skin of the tail is damaged. Cruppers are adjusted to engage only when needed; pressure is not meant to be constantly applied. If a crupper is too tight, it can cause severe chafing, discomfort and sores. If it is too loose, the saddle or harness may not stay in the proper position. If used in an improper manner for too long a period of time, the horse may even become disabled in the hindquarters. The loop of a crupper is kept very clean.

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