Yes, 5/16" O.D. Copper pipe. Most of it is bent out of shape, it needs a few fittings replaced but I can't identify the screwed thread. It's 1/2" dia x 24 TPI. Just wondering if it's manufacturers own thread. The carb is cast brass, never heard of maker. I'll get it later today.I bet all the fuel pipes are copper so no chopping out a blocked rubber pipe and replacing it with new.