Meets ADA requirements for Emergency Phones: Can automatically light the "Call Connected" LED for the hearing impaired Transmits a unique location I.D. code or voice announcement Grade 2 Braille label for the visually impaired Non-volatile digital voice announcer with 16 seconds of voice memory Advanced call progress detection Handsfree operation Phone line powered Non-volatile memory (no batteries required) Marine grade 316 stainless steel prevents corrosion on stainless models Dials up to 5 emergency numbers E-1600-20A and E-1600-52A dial up to 3 non-emergency INFO numbers Cycles through backup emergency and non-emergency numbers on busy or no-answer Optional Enhanced Weather Protection (EWP), EWP products are designed to meet IP66 Ingress Protection Rating, see DOD# 859 Hangs up on CPC, silence, busy signal, dial tone, time-out or touch tone command Programmable to auto-answer on incoming calls Remotely programmable Extended temperature range (-15 F to 130 F) 9 different chassis or board only available Available in 42 tall tower phone model E-1600A-BLT-EWP (DOD# 217) Central Station Monitoring capability (dials 2 numbers) Optional PB-100 Polling System available (DOD# 232) Optional BLK-3-EWP strobe light kit available (DOD# 653)