Gatekeeper is a 1U gate generator, with an adjustment knob for gate length and range switch.

Gatekeeper takes nearly any rising edge signal and outputs a gate of variable length. The module will not output another gate once the circuit is initiated until it reaches the end of the event as determined by the length knob. There is also a switch to choose between shorter or longer gates. Button down - lengths are from 0.1 - 5 seconds; Button up - lengths are from 0.25 - 10 seconds. Gate output is approximately 10V.

https://www.ottermods.com/gatekeeper-1u