https://www.sinohose.com/pin-lug-coupling/ Application: For liquid suction and discharge Material: Standard Pin lug coupling have aluminum shanks with brass swivel nuts and NPSM thread,NST(Fire hose thread)and pp are available Thread: NPSM,NST,NPSH Size: 1" to 6" Seal: NBR,EPDM Aluminium Pin Lug Coupling Aluminum/Brass Pin-lug couplings are built of lightweight aluminum with brass pin-lug nut for long lasting durability. Pin-lug style assures strength and reliability.