Panasonic KX-TA624-5 Advanced Hybrid Analog Telephone System with Caller Id CapabilityComes standard with 3 CO lines, 8 extensions (system or single line), and 4 intercom paths Caller ID Compatibility requires KX TA62493 card see expansion cards Built in 2 port Doorphone Opener Card Allows connection of many types of single line telephone devices such as answering machines, cordless phones, and fax machines System can be expanded to 6 COs by 24 stations with the addition of add on cards (KX TA62477 3) INITIALLY CONFIGURED FOR 3 COS, 8