Strobe flasher with visual / audible phone ringer
Flashing strobe & ringer provides visual and audible alerts for an incoming phone call. In addition to the phone ringing, the bright strobe visually alerts the hearing impaired that there is an incoming call. Also provides a visual signal in noisy locations, factories , workshops or simply when the stereo is at high volumes. Easily installed in combination with or without a phone.
Brand name(s) : GC Electronics

Features:
Compatible with analog telephone lines only , not for use with a PBX / digital phone system