Surcingle behind the withers. When used with a saddle, the surcingle runs over the seat near the pommel. A surcingle is also used over the top of certain types of pack saddle and pack to keep the pack bags and swag in place. A surcingle is usually used with a pad, and fit to the horse's back as carefully as a saddle would be. It is tightened enough to prevent slipping, more when used with a saddle and rider, less when used for ground training. Surcingle A surcingle is a strap made of leather or leather-like synthetic materials such as nylon
Girth (geometry) width, with the same width "w". All curves of constant width have the same perimeter, the same value "w" as the circumference of a circle with that width (this is Barbier's theorem). Therefore, every surface of constant width is also a surface of constant girth: its girth in all directions is the same number "w". Hermann Minkowski proved, conversely, that every convex surface of constant girth is also a surface of constant width. For a prism or cylinder, its projection in the direction parallel to its axis is the same as its cross section, so in these cases the girth