The Comtek AT-216 has a micro-mini jack for use with the M-4020P plug-in environmental microphone for either the Enviro-Mic or Smart-Mic. This input jack may also be used with other accessories such as handheld directional microphones, clip-on speech training microphones, and telephone adapters. It works as a remote microphone, overcoming common listening problems for those with hearing loss: background noise, reverberation and distance from the speaker.
A higher signal-to-noise ratio plus a higher frequency response of the FM signal work together to maximize the performance of hearing aids, cochlear implants, and earphones. In addition to t-coil hearing aids, the user wears the personal receiver and neckloop. If hearing aids are not used, the receiver and headphones may be used instead of the neckloop.