Polycom VoiceStation 500. Voice codecs: IEEE 1329-1, Frequency response: 300 - 3300 Hz. Input voltage: 110 - 220 V, Input frequency: 50/60 Hz. Dimensions (WxDxH): 235 x 242 x 76 mm, Weight: 570 g. Certification: NA CI/C-UL, FCC Part 68, FCC Part 15 Class B, Canadian ICES-003, CE Mark (R & TTE),. Operating temperature range (T-T): 5 - 40 °C, Operating relative humidity range: 20 - 85 %, Storage temperature range (T-T): 30 - 55 °C