Slotter & Co. of Philadelphia manufactured rifles as well as their copies of Henry Deringer's famous pistols for A.J. Plate of San Francisco from 1860 to 1871. Plate immigrated from Germany in 1835. He established his business in San Francisco in 1850; it quickly grew from simple sales booth to a large shop by 1855 and became one of the most important western gun dealers. "SLOTTER & Co. PHILA" is marked on the back action lock plate, and the top of the barrel is marked "SLOTTER" at an angle, "MADE FOR" parallel to the bore, and "& Co. PHILA" over "AJ Plate/SAN FRANCISCO." The upper left flat at the breech is marked "GAIN TWIST/WART/620," and the underside of the barrel is marked "REMINGTON" and "23." The barrel has dovetailed blade and notch sights. Several other components are also marked "23." The rifle also features double set triggers, trigger guard with a grip extension, a cap box marked "SLOTTER/& CO./PHILA" on the inside of the door in large letters, and a straight wrist stock with brass forend cap, single wedge, cheekpiece, and brass butt and toe plates.