2 1/4" X 3 1/4" API Pin cable spudder thread to API rotary well drilling tool joint
(5 threads per inch, around 3-1/4" to 3-1/2" pin length, around 2" or just slightly larger pin I.D.),
Around 21" shoulder-to shoulder length
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.