3 3/4" x 2 3/4" - 7 threads per inch box female to 2 1/4"x 3-1/4" pin male crossover sub adapter drill stem extension
For cable tool well drilling servicing rig.
Presumably American manufactured with carbon and/or alloy steels, but unsure if this is Acme, Spang, Gill Rock Drill, Ideco, Trident, Rampp, O.W.S. Co., Keystone or maybe another historical tooling manufacturer
If you require thread protector(s) on tool joint(s) add another $15