What is the thread on 109 brake steady post?

[KingSlug]

I need to swap out some 109 brake steady posts? I meant to get it last night but forgot, I am at work now and hoping to get bolts tonight.

What is the thread and pitch on the steady post? Please dont say they are whitworth.

Jared

[jac04]

IIRC, they are UNF threads. I bought new steady posts, and remember using hardware store UNF nuts on them.