Arrow MK31 Communicating Knob Lock

Arrow MK31 Dead locking latch bolt operated by knob from eitherside. Turning key in either knob locks or unlocks its ownknob independently. Do not use on doors in rooms thathave no other entrance. Arrow's MK Series offers security professionals simple solutions to accessibility requirements. The MK Series designs, architectural finish, and available function options make it ideal for commercial applications where heavy-duty Grade 1 hardware may not be necessary. Features Lock Chassis: Cold rolled steel with zinc dichromate finish for corrosion resistance. Requires standard 2-1/8" (53.97 mm) bore through door.Backset: 2-3/8" (60.32 mm) standard. 2-3/4" (69.85 mm), 3-3/4" (95.25 mm) available.Door Thickness: 1-3/8" (34.92 mm) to 1-3/4" (44.45 mm)Latch: Brass with 1/2" (12.7 mm) throw. Latch housing is steel, with zinc dichromate finish for corrosion resistance. 7/8" (22.225 mm) bore in edge of door is required.Latch Front: Brass or bronze. S