The old indicator handle broke. Using these spares allows me to continue using the lamp(s) as that was all that was wrong with it. The only thing I didn't like is that it doesn't fit as snugly as I would like, but that's NOT the fault of the replacement switch. You just screw them all the way in, and then the switch turns the light on and off as you try to screw it down. However, it still works fine.