ViSYS two-line phone works great alone or build your own system. Wirelessly connects multiple RCA two-line cordless or corded/cordless phones to create a system of up to ten devicesno additional phone jacks required. Features duplex speakerphone with DECT 6.0 technology. Call waiting/caller ID, 99 name/number caller ID directory, ten one-touch speed dial buttons. Do Not Disturb with variable length settings. Call conferencing with call timer and call transfer. Desk or wall mountable.