UNION 33/64"-18T
A.M. STD. 1/2"-20T H: 7/16"
REPCAL H:1/4" (NO THREAD)
CRANE 9/16"-28T H: 3/8"
INDIANA 1/2"-28T H: 13/32"
AMERICAN ELJER 1/2"-20T H: 11/32"