Listen Technologies LR-4200-IR - Intelligent DSP IR Receiver for ListenIRThe LR 4200 IR receiver from Listen Technologies offers outstanding audio clarity and quality with the best range and reception in its class. Part of our Intelligent Digital Signal Processing (iDSP) line, the LR 4200 IR is the smallest device of its kind, resulting in a compact unit that wont burden the end user. An integrated neck loop lanyard makes each receiver easy to wear, and the DSP loop driver offers an improved listening experience for anyone