Replaced the head (just a tube cap with a hole drilled in it) from wine bottle washers. At first I tried 1/2 in. atomizers but the pump ( basically a rebuilt aquarium pump) wasn't providing enough pressure, also the screw base wouldn't fit a narrow mouth bottle.Swapped for this 3/8" block and installed a 1/2 to 3/8 adapter on the pump outlet and couldn't be happier when i see this thing spinning happily and removing all the dirt from my glassware.