Flap valve type but with corrugated bottom like sand pump
For cleaning 4" + wells with cable tool drill service rig etc.
Around 8' overall length not counting extra link on top
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