unrestored c. 1880's original and fully functional exterior residential entrance or vestibule door "crisscross" pattern mortise lock designed and fabricated by the p. & f. corbin co., new britain, ct. the mortise lock contains an ornamental brass faceplate with lightly incised designs highlighted in black enamel. the two stop buttons are original and intact. the lock box retains the original thumb twist or night latch handle with matching circular-shaped rosette. the cast iron case retains the original baked black enameled finish. the corbin initials are lightly embossed above the keyhole. 1 1/4 inches x 3 1/2 inches x 6 inches.