A leather satchel holding the daily tools of mount care: an iron currycomb, a stiff dandy brush and a soft body brush, a hoof pick on a turned handle, a mane-and-tail comb of carved horn, a sweat scraper, a bridle awl with spare waxed thread, two or three lengths of spare strap leather, a small tin of hoof oil, a bar of saddle soap, and a folded rag. Ostlers, drovers, and any cavalryman who has spent a winter on the road carry such kits; a horse that is curried daily works longer and sounder than one that is not, and a saddle kept oiled outlasts one left to salt-sweat and rain.
The kit is not the saddle or bridle itself — those are gear the rider carries separately — but the difference between tack that parts in a charge and tack that holds. A cavalry trooper without a brush and an awl is a walking trooper within a month.