US beer nut (hex tailpiece nut) (7/8"-14 (1" hex))
Where 7/8"-14 (1" hex) is used, its real dimensions, and how to connect it to other keg fittings.
Published dimensions
- Designation
- 7/8"-14 (1" hex)
- Size / thread
- 7/8"-14 straight thread, 1 inch hex across flats
- Fitting form
- internally threaded hex coupling nut
- Seals on
- compresses a rubber washer between the tailpiece and the shank end
- Rating / role
- the US beer industry standard nut that secures a tailpiece to the back of a shank
Used on: the back of every North American beer shank; it tightens a tailpiece, elbow or coupler tail against the shank.
The beer nut is a 1 inch hex with 7/8-14 internal thread, the same thread US homebrew shops loosely call 5/8 BSP. It does not seal on the thread; it squeezes a flat washer between the tailpiece and the shank face, so a weeping beer nut means a missing or flattened washer, never a thread that needs tape.
Flare fittings seal on the 45 degree flare face and must never be taped. Push-in fittings seal on an O-ring against the tube wall and need the tube cut square. Barbs seal under a worm clamp. Getting the sealing method right matters more than the thread label, because most homebrew leaks are a taped flare or an unclamped barb.
Connect this fitting
Sources: American Homebrewers Association: the anatomy of a beer faucet (7/8-14 shank, beer nut, tailpiece, washer) ยท Installation Parts Supply 7/8-14 (5/8 BSP US beer industry standard) beer nut / tailpiece nut