Longest range cordless with 2-way radio independent of base unit. Expandable system - up to 4 lines (with 4 base units) and 36 handsets. Call manager - program your handset by individual base unit to receive calls. Audio in jack for music/sales message on hold. Vibration mode. 4 line illuminated LCD. Caller ID with call waiting - stores 20 calls. Frequency hopping security - 200 times per second. Digital privacy and clarity. 3 hours talk time / 40 hours of standby time. Call transfer - announced or unannounced. Hold, mute, flash, redial, call timer. 30 name/number speed dial directory. 6 level volume control. Any key answer.