"My grandpa got it from a friend but they both don’t even know what it is. This might be a part of some bigger welding machine but I’m a total noob. Anyone know what it is?"
A: "Normal small portable welding inverter (electrode welding), no bigger machine needed."
If I remember correctly that's a book holder, two straps are used to hold the books and that's the handle.
Used on a siphon hose to keep air from entering the vine wile not used, thus preventing vineger growth.
My Dad had some, he'd get them out when we went ice fishing!
Don't Google it, Duckle it!