Bulldog clip

A bulldog clip is a device for temporarily but firmly binding sheets of paper together. It consists of a rectangular sheet of springy steel curved into a cylinder, with two flat steel strips inserted to form combined handles and jaws. The user presses the two handles together, causing the jaws to open against the force of the spring, then inserts a stack of papers and releases the handles. The spring forces the jaws together, gripping the papers firmly.