RF IDEAS RDR-6081AK5 pcProx Enroll Proximity Reader Type: RFID Reader Form Factor: Desktop Frequency: 125 kHz Connectors: Serial RS-232 Power Supply: USB self-powered Dimensions: 3.38 x 2.00 x 0.60 Weight: 0.45 lbs. Operating Temperature: -22 degree to 150 degreeF (-30 degree to 65 degreeC)