A27. 14x1 female spigot right
Links to photos of examples:
This valve configuration was original on Yamaha QT50, early Yamahas and Hondas, and early Taiwan mopeds. It can replace other 14×1 thread valves, in most cases.
This motorcycle fuel valve has a 7.7 mm spigot, for 1/4″ (6.3mm) fuel hose.
Honda Design: Note that the little arrow on the handle points opposite to the handle. So off is arrow left (handle right), on is arrow up (handle down), reserve is arrow down (handle up).