True bypass ABY amp selector with tuner out On-board transformer to eliminate ground buzz 180° polarity reverse to phase-match amps Compact and rugged for pedalboards Plug and play easy to use Designed for the purist, the Radial BigShot ABY is an ultra compact, 100% passive foot switch that provides true bypass ABY amp switching capabilities with A or B toggle and A + B combine functionality. This assures the guitar signal is routed directly to the amp without any buffering, loading or tone altering circuits. To add versatility, the BigShot ABY has a built-in transformer that can be engaged to eliminate troublesome ground loops. Once on, you can also ensure your two amps are properly in phase using the 180º polarity reverse switch. The compact yet ultra rugged design makes the BigShot ABY ideal for pedalboard designs where space is always at a premium. Furthermore, because it does not require powering to make it work, it eliminates the need for batteries and space hungry power supplies.