I've never seen these lubrication fittings before, they were certainly overdue.

A 5/16" eyeball joint, the fittings is barely 1/8" in diameter. In this application what is being lubricated, the threaded bore, the eyeball, or both?

They're called flush-mount grease fittings but I see no mini-gun to fill them.

A 5/16" eyeball joint, the fittings is barely 1/8" in diameter. In this application what is being lubricated, the threaded bore, the eyeball, or both?

They're called flush-mount grease fittings but I see no mini-gun to fill them.