The Zoom FS01 is an easy-to-use footswitch for use with lots of Zoom products. For example, the FS01 will let you switch between two effects patches on your Zoom Fire amp. Switch between a clean sound for rhythm parts, and an overdrive tone for leads. It is compatible with the following Zoom products, and more: 503, 504, 505, 506 ,507, 508, 509, 510, RT323, RT123, RT234, RFX2000, 2020, 3030, 4040, 1202, MRS1044, 4040, 9120. Use with the Zoom RT223 Drum Machine. When connected to the RT223, the FS01 lets you rock out live, triggering patterns with your foot. You can also use the switch to start or stop a pattern, perform tap input to specify the tempo, trigger the bass drum sounds, switch between hi-hat open/close, and much more.