This attachment allows you to connect a beer hose to the faucet side of a shank.

The threaded faucet adapter can be used to clean two beer lines at once if you have two faucets next to each other. You can connect the beer lines using two of these fittings and a piece of 3/16' I.D. hose that would reach between the two faucets. The cleaning solution would then go up from the bottom of one beer line through to the second shank and down through the second beer line. It can also be used to attach a cleaning kit to the faucet coupler to pump cleaning solution backwards through the line.