Gents, I have been asked to test and cerify a boiler (LBSC Bantam Cock) and the pump connection bushing is a 3/8-26 thread. This isn't a standard thread for anyone . . . even Tracy Tools lists it as a special. What in the world thread series does this come from? Is this one of those cycle threads I always heard about? I also hope everyone has had a very pleasant and safe holiday. Regards, Harry Wade Nashville Tennessee MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.