This is a stainless steel American Sanke coupler. It includes a beer nut, 5/16" tailpiece, and check valve for the air side. It does not include a beer nut, tailpiece, or beer washer for the liquid side. Most beers brewed in the US and Canada use an American Sanke coupler. Sometimes called a tap.
Fits D system keg valves.
A short non-complete list of brewerys and beers that use the D system:
Abita, ACME, Alaskan, Allagash, Anderson Valley, Avery Reverend, Bad Frog, BayHawk, BBC, Blue Moon, Breckenridge, Brooklyn, Bruin, Bud Light, Budweiser, Busch, Carlsberg, Castle Maine, Celis, Cider Jack, Clipper City, Columbia Brewing, Coors, Coors Light, Corona, Deschutes, Devil Mountain, Dogfish Head, Dos Equis, Duchesse de Bourgogne, Eel River Brewing, Ellicottville, Eurobrew, Fat Tire, Firehouse, Firestone, Flying Dog, Foster's, Full Sail, Genesee, Goose Island, Gordon Biersch, Grant's, Great Divide, Green Mountain Cidery, Hamms, Hard Core Cider, Harpoon Ale, Henry Weinhard's, High Falls, Highland, Holy Cow Red, Hornsby's, Hudson Valley, Humboldt, Ice House, Killarney, Killian's Irish Red, Kirin Ichiban, Kokanee, Labatt Blue, Lagunitas, Leinenkugel, Little Kings, Lonestar, Lost Coast, Mad River, Maudite, Michael Shea's, Michelob, Mickey's, Miller, Milwaukee's Best, Modelo, Molson, Moosehead, Natural Ice, Natural Light, New Amsterdam, New Belgium, North Coast, O'Doul's, Old Dominion New River, Old Milwaukee, Old Vienna, Oskar Blues Dale's Pale Ale, Pete's, Portland, Pyramid, Razors Edge, Red Ale, Red Dog, Red Hook, Red Wolf, Rogue, Rolling Rock, Saint Bernardus, Sam Adams, Saranac, Saxer Brewing, Scaldis, Schmitt's, Shiner Bock, Ship Inn, Shipyard, Sierra Nevada, Strohs, Tecate, Thomas Creek, Thomas Kemper, Tommyknocker, Trois Pistoles, Tucher, Unibroue, Wasatch, Weinhard's, Whitbread, Widmer, Woodchuck Dark & Dry Cider, Wyder's, Yuengling