The B-01S is an input module for use with TOA 900 series amplifiers. It has a removable terminal block connector and supports line level signals. It can accept balanced or unbalanced equipment such as CD players, tape decks, or AM/FM tuners. Transformer isolation minimizes ground loop problems when connecting remote equipment. Simply plug the B-01S into the module slot on your 900 series amplifier and you're instantly ready to connect a line level terminal block input.