The Growler Filler Spout extension can be used on any of the Nukatap beer taps. It is also compatible with Intertap taps. The spout has a 13mm barb which you can attach some hose so you can fill your growler from the bottom up to minimise foaming. Simply un-screw the regular nozzle and screw on the Growler Filler Spout with hose attached and use as you would a growler filler tap. Note: not compatible with Krome taps, use the Jug-Growler Filler instead.