Temperature 0 to 40 degrees Celsius; Humidity: 10% 90%; Frequency Response: 3403400Hz, +/ 3db; Connections: RJ 11/RJ14 line inputs, USB 2.0 (12Mbps) Recording Trigger: Phone line off-hook voltage<20vDC>, VOX from 0.1 Vpp to 0.8 Vpp Line Impedance: >10M ohm DC, >10K ohm AC; Ringer Equivalence: less than 1.0; Capacity: 10,000 hours, 65,536 files, HDD; Security: Password (3), Master, PC, & keypad; Display: Built-in, 2 1/8″ x 3/4″, backlit LCD + PC; Speaker: Built-in, with an external audio jack; Size: 6 5/8″ x 8 1/2″ x 2 3/8″, 3.7 lb.; Power Requirements: AC 220 volt