Supports up to 500 users; Access via proximity card and/or PIN code; Operating Voltage Range: 12–16 VDC From a regulated power supply; LEDs: Two tri-colored LEDs; Compatible Cards: All 26-Bit EM proximity cards; Maximum Reading Range: 90 mm (3.5 in.); Operating Environment: Indoor use; Operating Humidity: 0% to 95% (non-condensing)en