Stirrup Leathers
Because a rider must be able to move his or her legs while riding, stirrups cannot be attached on the body of the saddle itself, but rather must be attached in a manner that allows the rider's leg a full range of motion. Therefore, stirrups are attached to a saddle by means of adjustable straps, called stirrup leathers. Depending on the design of a saddle, stirrup leathers may be attached to a "stirrup bar," a small forged steel bar embedded into the saddle tree, or may be wrapped around the bars of the tree itself. Because different riders are of different heights, and stirrups also may need to be adjusted up or down to accommodate different types of activity, stirrup leathers have buckles and holes that allow length to be adjusted.
On an English saddle, leathers are quite thin, only about one inch wide. On a western saddle, they are very heavy, three to four inches wide on the side closest to the horse, and even wider, expanded into a decorative "fender" on the outside (which also protects the rider's legs from the sweat of the horse). Stirrup leathers on other saddle designs fall in between the extremes represented by the English and western saddles.
Stirrup leathers are usually manufactured so that the smooth side of the leather faces the wearing surface, as the smooth side wears less quickly than the rough side. There are also modern alternatives to leather, including nylon, plastic covered nylon (biothane being one example) or leather over a nylon reinforced core. These new "leathers" may last longer and also resist stretching. On the other hand, they may chafe and rub the leg, and poorly made products may break more easily than leather.
As the rider's whole weight must be carried at one side when mounting, on an English saddle, one stirrup leather often becomes stretched longer than the other, usually the left one, because most mounting occurs on that side. While a simple adjustment of the leather can even up the stirrups, to preserve the integrity and longevity of the leathers, they should be switched to the opposite sides from time to time. On a western saddle, with a heavier, permanently installed fender and stirrup leather that cannot be switched, stretching is slower and less extreme, though it also occurs in this type of saddle. Any unevenness in the leathers can be managed by adjusting the stirrup length, and if necessary, by adding extra holes in the leathers to allow them to be buckled at an intermediate point between the existing prepunched holes provided by the saddle manufacturer.
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