This simple module is a dual manual gate. Each gate outputs a constant 0V signal until the button is held down at which time the output level jumps to a user specified level anywhere in the range ±10V. Releasing the button returns the output voltage to 0V and hence closes the gate.
It can be useful for interactive firing of events during a performance.
It also has a latch mode where pressing and releasing the button will open the gate and a subsequent press and release will close the gate.