These type of clamps are also known as worm gear clamps or gear clamps. They are generally used for attaching and sealing hosing or tubing.
Ideal worm drive clamps are generally used as a type of fastening tool. They use a hex screw as a way to connect the band in a circular formation. When there is a hose, for example, that is leaking liquid or gas these can tighten the connection by turning the hex screw.