For residential single and multi-family bed/bathroom doors Pushbutton locking, open from outside with small tool; turning inside knob releases pushbutton 1 piece knob for better security and appearance Solid brass trim and all metal parts 3 piece assembly for easy installation DUAL OPTION UNIVERSAL: Fits all doors, 2-3/4 or 2-3/8 backset; 1-1/8 square corner, 1/4 round corner, or circular drive-in preps mbly for easy installation DUAL OPTION UNIVERSAL: Fits all doors 2-3/4 or 2-3/8 backset; 1-1/8 square corner 1/4 round corner