A Hose Clamp or hose clip also known as a hose lock, is a device used to attach and seal a hose onto a fitting such as a barb or nipple.Hose clamps are not to complicated to figure out. Firstly expand the hose clamp by turning the screw counterclockwise, just large enough to slide over the hose.Now slide the hose clamp over the hose.The fitting that you want it to fit into, slide it over the hose.Slide the hose clamp over the joint between the fitting and the hose.