4-Line Operation.Expandable to a 10 Station System.Intercom and Call Transfer Between Desksets, Handsets and Base Station.3rd Party Conferencing.Requires SB67118 or SB67138 Base to operate A contemporary workhorse, the AT&T SB67148 cordless deskset extends small business communication. It supports up to four lines with unique ringtones, caller ID/call waiting and voicemail. DECT 6.0 Digital technology delivers extended range, sound quality and security, while ensuring wireless networks and electronic devices don't interfere with conversations. In fact, Wyle Labs, an independent laboratory, has confirmed that AT&T DECT products perform up to 45% better in range competitions against similarly equipped phones from the leading competition. A speakerphone makes hands-free communication easy. Three-party conferencing and speed dial memory for up to 10 numbers make this the perfect phone for any bustling small business. Intercom, call-transfer and conference capabilities further streamline communication. The AT&T SB67148 can expand to accommodate up to 10 cordless desksets or handsets. It requires the AT&T SB67118 or SB67138 base to operate.