The device is supplied with a clip that fastens it to a belt or guitar strap. It uses a single 9-volt battery, providing an average life of 50 hours. The output of the B 29 L can be switched either to mic or line output level, depending on the downstream requirement. Both inputs to the B 29 L are mini-XLR-F, and the output is a standard XLR-M. The B 29 L effectively makes one output out of two. It is indispensible with small mixers, where it can expand the number of available inputs. In addition