【IN-USE/VACANT Indicator】Lock/Unlock with thumb turn button from inside, Unlock with emergency key from outside. The colorful indicators are very visible that can effectively remind people of the use of the room. 【Reversible】both left & right handed. 【70mm Brass Backset Latch】2-3/4inch backset fits door thickness from 1-3/8inch to 2inch. The small hole on the latch core can effectively prevent rust caused by water, and it can also oil the latch core through the small hole to make it work more smoothly. 【Heavy Duty & Security】About 1.22lb per pack. ANSI/BHMA 156.2 Grade 2 Certified and UL3 Hours Fire Rated. ADA Compliant. 【Material&Finish】Zinc Alloy&Stainless Steel. Satin Chrome 26D Finished. grade 2 commercial deadbolt with thumb turn button lock