✔️ COMPATIBILITY - PLEASE NOTE THIS PHONE CANNOT WORK ON ITS OWN - This additional handset is compatible with the Geemarc phones from the 595 and 595 U.L.E range, which include the DECT595 Combi, the DECT595 Photo, the DECT595 Photo Duo, the CL595, the DECT595 U.L.E, the DECT595 U.L.E Duo and the DECT595 U.L.E Doorbell. Up to 4 additional handsets can be paired with a DECT595 main phone base, and up to 3 with a DECT595 U.L.E main phone base. 👂 HEARING AID COMPATBLE - This product is designed for people with medium to severe hearing loss. If you are wearing hearing aids and wish to use them while on the phone, simply put your hearing aids on the “T” setting. 🔊 EXTRA LOUDER RINGER - You will never miss a call thanks to this phone's 80dB loud ringtone. To give you an idea, this is more or less as loud as a vacuum cleaner or a power lawn mower. 🔅 LARGE BACKLIT DISPLAY AND BUTTONS - This phone's white backlight makes reading the alphanumerical characters on the display super easy, while the 9 to 10 mm high digits on its large and widely space buttons prevent you from ever misdialling. 📢 VOLUME BOOST CONTROL - This phone has 6 amplification levels and is equipped with a boost button that allows the user to increase the receiver volume up to 50 dB during calls. 🆘 SOS FUNCTION - The handset has a red emergency button which when pressed, activates the SOS function of this phone. Once the SOS function is activated, the phone automatically calls the four numbers you have pre-set, one by one, until someone answers. 🆔 CALLER ID - Know who is calling you! Providing it is supplied in your current package by your service provider, this phone will display Caller ID! Included components: battery pack, ac adapter