5" Tapered Sofa/Chair/Ottoman Wood Furniture Leg Set Of 4 Used *Read Description

Attached by threaded rod. Approximately 1 3/8" long. I was able to use a 5/16-18 gage unto the thread, but there was a little slop. It's definitely an 18 pitch thread but it could be metric size. The rod itself measured at  0.301" diameter which is around 7.6 mm.