Grandstream DP730 specifications: supports up to 10 SIP accounts, and up to 10 lines. Screen size: 2.4-inch (240x320) color TFT LCD. Ports: Micro-USB port. 27 keys including 3 soft keys, 5 navigation/menu keys. 3-color MWI LED. 3.5mm headset jack. Power ports: Universal Power Supply Input AC 100-240V 50/60Hz; Output 5VDC 1A. Micro-USB port for alternative charging and non-battery operation. Rechargeable 1500mAh Li-ion battery (500 hours of standby time and 40 hours of talk time). Dimensions: 168.5mm (length) * 52.5mm (width) * 52.5mm (height). Weight: 465 grams. Operating temperature: -10º to 50ºC (14 to 122ºF). Features: call hold, call forwarding, call transfer, 3 audio conferences, intercom, phonebook, call waiting, call log, auto answer, noise cancellation, screen sleep during call.