I Since I needed a cheap way to control my router and dust vac, especially now that it’s hidden away in a cupboard, I was pleasantly surprised to stumble across these at Harbor Freight for less than $20.
Picked up one for each, and they work great. Can shut off the spindle, hands free, and keep the vacuum going as long as I need to.
They also have a momentary version. This one is latching. Click on, click off.