Sentry Supply 656-2702 Concealed Latch Knob Set, Cast Zamak, Chrome Plated, Security Fastener, Pack of 1 Set Used to replace broken or missing knob sets of concealed latches in 1 in. thick partition doors. For use as a privacy lock in toilet partition stalls Outside diameter of 1-5/8 inches Chrome plated finish Zinc alloy (cast zamak) construction The fastener included with this kit features a tamper resistant T-27 Torx security drive