One of the original Metallic Compression Casting Company's designs. The company was later purchased by Russell & Erwin. Shown in 1875 Russell & Erwin catalog, page 378. 2.5”/$6.00, 2.25”/$5.00 pair. Patent design # ​D4,131, June 7, 1870 by J.J.C. Smith.K-10700is a variation of this design by Hopkins & Dickinson. Escutcheon shown with knob patent# D3825, January 25, 1870 by Joseph A. Ruff. Escutcheon pictured has been damaged and key cover lost.