The KX-T7700 series includes 4 telephone models and one DSS console, all available in white and black, providing numerous options to suit each individuals needs and budget. The KX-T7720, KX-T7731, KX-T7740 and KX-T7750 are all designed for use with the Panasonic Advanced Hybrid Telephone Systems and our Digital Super Hybrid systems, allowing you to upgrade the system without changing out the telephones. The top of the line, 24-button, 3-line backlit display KX-T7736 telephone was designed to work exclusively with our KX-TA624-4.