Boss FS-5U Momentary Foot Switch
The FS-5U (momentary type) engages a function while you hold down the switch.
(There are two types of BOSS footswitches to chose from depending on the application. The FS-5U (momentary type) engages a function while you hold down the switch. The FS-5L (latch type) changes the on/off status each time you press the switch).