U.S. Pattern 1874 Dyer Pouch

Designed by Brigadier General Alexander B. Dyer of the Ordnance Department, this pouch was issued to mounted troops.  The cartridges are held loosely in the fleece-lined pouch. 

Our specimen has "US" embossed on the front of the flap.  The front of the pouch under the flap is stamped "WTZ", presumably an inspector's initials.