The G-Tel EP-3500 Armored Emergency Hotline Phone is designed for locations where an emergency hotline / speed dial access is needed and protection and durability are important.Made of durable 14-gauge stainless steel with tamper resistant locking system.This phone is perfect for use as an emergency phone or as an incoming-calls-only phone for industrial applications.Heavy-duty armored handset is hearing aid compatible (HAC) and has an anti-static receiver, additional lengths and options available. Noise-Canceling Microphone option is recommended for loud environments. The EP-3500 is also weather resistant.