Sep 6, 2007 #1 PROEGUY Mechanical Joined Dec 21, 2000 Messages 24 Location US what does the "R" in UNRC-3A or UNRF-3A mean in a thread callout. TIA
Sep 6, 2007 2 #2 doct9960 Mechanical Joined Aug 15, 2006 Messages 618 Location CA http://www.ring-plug-thread-gages.com/ti-UNR-vs-UN.htm Upvote 0 Downvote