Telephone line powered- Hearing aid compatible amplified handsets- Rotary handset volume control- 1-32 digit programmable speed dial number- Touch Tone and 10/20 pps pulse dialing- Non-volatile E2 memory no batteries required – Restricts fraudulent calls from hand held dialers- K-1900D/W-2 available in red or ash- Optional Q170600 ringer Fax Back Doc 845- Operates on a C.O. line or analog PABx/KSU extensions- Ring detection will not dial on incoming calls- Programmable security code to enter programming mode- Touch Tone programmable- K-1900-6 fits standard 500, 554, 2500 and 2554 set phones