Lockwood 530 Entrance KnobsetLockwood 530 Series Commercial Grade, Entrance Knobset, Tulip Knob. Entrance Function Outside key locks and unlocks both knobs. Inside turnsnib locks and unlocks both knobs. Additional Information Satin chrome finish Compatible with most restricted keying systems 60mm backset standard 70mm and 127mm latches available separately Suit door thickness 32 48mm Brass latch bolt with 13mm projection Knobs and roses made of high purity zinc alloy Fire rated