The Mackenzie ICM-25 is an Input Control Module which extends the start contact capability of Mackenzie audio messaging systems. Each ICM-25 offers 25 individual start contacts to initiate playback on RS-232 equipped systems such as the MacFi-mp and M2. These systems typically offer a limited quantity of start contacts(8-10) due to space limitations, but have greater message storage capacities(99-256). The ICM-25 is powered by 12VDC which may be sourced from the host unit or directly from a transformer.