I first saw this at in 2016 at Rusty Keeler’s NAEYC Conference session. He gave it out as a prize. Basically it allows a kid to easily use it without letting the water just run and run.
https://earthplay.net/product/simple-faucet/
The kids simply press the little switch and the water dribbles out. When they release it, the water stops! Perfect!
I use this at our feet rinsing station.