This double ended spigot with 1/, 4/20 and 3/-8 " male thread on the setting designed to be universal for both 16 mm (5 8/in diameter and 1/4 the size of the o clock.-20 and 3/8 " male thread
Thread Size: 1/4 in.-20/male, 3/8 " male
5/Diameter 8/16 mm