This is a leather priming flask or shot pouch.

A priming flask usually carried a small amount of gun powder to prime the pan on the lock ready for firing. A shot pouch was used to carry pistol or musket balls for firelock weapons in the 17th and 18th centuries. They would usually be tied onto your belt or bag so it was easy to access.

This flask can be fitted with either a wooden stopper or a spout and stopper.

It is 2.5" wide and 8" high with a 17" leather lace.

(One supplied)