For residential single and multi-family bed/bathroom doors. Pushbutton locking, open from outside with small tool turning inside knob releases pushbutton. The knob for better security and appearance. Solid brass trim and all metal parts. Assembly for easy installation. Dual option universal fits all doors, 2-3/4 inch or 2-3/8 inch backset 1-1/8 inch square Corner, 1/4 inch round Corner or circular drive-in preps.