Panasonic KX-TGE275S 5-Cordless Handsets Link2Cell Bluetooth Corldess Phone with Answering Machine, Silver Panasonic High Quality, Office Phone ALERT,TALK CID,ADV TAD,DK Ergonomic Design Energy Star Certified. Link2Cell Bluetooth Enabled Speakerphone (Volume Steps)-7-step and 8 step. Ringer Volume Steps-6+OFF. Receiver Volume Steps-5. Frequency-1.9 GHz. Frequency Range-1.92 GHz - 1.93 GHz