Atrium door mortise lock,single unit assembly with reversible latch key operated outside. Turn knob operated inside rekeyable 5 pin. Tumbler cylinder with SC1 keyway. Double locking with spring latch and deadbolt. Solid brass or chrome face plates 1-1/8"W and 8-1/4"H .   two solid brass or chrome levers that are  4-1/2"long and fits all doors from 1-3/8" thick. Narrow stile backset 1-3/4 inches. forged solid brass. Packed with template and instructions. if you are replacing an existing atrium lock. this is a exact replacement a very simple installtion.