A Conveyor Belt Puller.
A colliery conveyor belt puller.
Made of iron. Size 5″ x 5″ x 3″ inches.
This tool was used to pull the lengths of conveyor belting along the structure ready for stitching together. The mechanism is pivoted in a way that the grip on the jaw is tightened by pulling the handle. There is a small grub-screw on the grip which can be tightened or loosened for grip on thick or thin belting.
I am unsure of the date of production though tools like this are still being made for the industry at present.