RDL Passive Audio Divider/Combiner 600?

RDL STD-600 is a 600 Ohm STD module, a resistive branching network with RF filtering on each of the four channels. Any channel (balanced) may be either an input or an output, combining stereo signals into mono inputs, splitting mono signals to multiple inputs, and even combining microphones with output shorting switches into a single Amplifier input. 150 Ohm and 10 kOhm STD modules also available. Radio Design Labs/RDL is a manufacturer of electronic audio, video and control products headquartered in Prescott, AZ. Their products are used in commercial and residential audio and video installations and in broadcast and recording facilities. The company is known as the pioneer of application-specific electronic modules including STICK-ON, RACK-UP and FLAT-PAK.