The Boss FS-5L and FS-5U are two popular foot switches for guitarists, keyboardists, and more. The FS-5L is a latching foot switch, while the FS-5U is an unlatching one. In this comparison post, you’ll learn about the differences between these two foot switches and which one to get for your setup.\nBoss FS-5L The Boss FS-5L is a latching foot switch. This means the foot switch will turn on when it’s pressed, and will stay on until it’s pressed again. The FS-5L has a red indicator light that illuminates when the foot switch is in the on position.\n When to Use the FS-5L Switching channels on an audio switcher like the Radial SW8. Switching channels on a guitar amp. Activating long term effects. Boss FS-5U The Boss FS-5U is an unlatching or momentary foot switch. This means the foot switch will stay on only when it’s pressed. Since the FS-5U is always off when it’s not pressed, it does not have an indicator light like the FS-5L.\n When to Use the FS-5U Advancing patches on a keyboard or keyboard rig. Triggering a sound effect on a sampler. Using a foot switch for tap tempo. Sustain pedal for a keyboard. Activating momentary effects.