Bass/Watneys G-System Keg Coupler
The G system beer keg coupler gets its name from the English developer Grundy. The valve face is like a circle with three sides cut off. This G system beer keg coupler is used by the following breweries: Anchor, Bass, Boddingtons, Fullers, Grolsch, Old Speckled Hen, Tennents, and Watney's.