Girth
As this is the means by which your saddle stays in place, it’s a pretty necessary piece of equipment, but of course, there are many different girths to choose from.
Your choice will largely depend on your discipline and the type of saddle you have (shorter dressage girths for dressage saddles, stud girths or jumping girths for showjumpers and eventers in order to protect the horse’s belly from stud injuries etc).
Girth size will also depend on the build of your horse, and if your horse is skin sensitive you may want to look for a sheepskin sleeve to go over an existing girth or buy a neoprene girth instead of leather.
As with all tack items, girths are constantly evolving to improve performance and horse comfort, so some girths now come with an anatomic cut that allows the horse to move the shoulders more freely, or they offer improved pressure distribution via a wider cut.
Oh, and if you have a Western saddle, you won’t be wanting a girth at all, you’ll need a cinch: a length of fabric that passes beneath the belly and attaches to the saddle at the latigoes – the long, thick straps of leather on either side of the saddle. The three most common materials for cinches are fleece, mohair, and neoprene.