The Louroe Electronics PTA-1 Portable Test Amplifier Kit is a battery operated audio amplifier kit used to conduct quality checks of microphone connections during installation and periodic field checks. It will work with a single microphone or at the output of a MLA-6 mixer/combiner. This kit contains a 1.25" speaker and 6' lead wires with alligator clips for testing connections, and 2 9V batteries.