A hand riveter is a manually operated tool used to install blind rivets. This tool group includes tools which are hand operated and hand powered and those that are hand operated and pneumatically powered. Both types are used to install blind rivets and both function in the same way. The tools expand and lock a hollow rivet by pulling a mandrel through the rivet body. The mandrel is then broken off and discarded, leaving the expanded rivet to secure the work pieces. Hand riveter tools are generally designed for use with blind rivets only and work by pulling the rivet mandrel through the rivet body to expand and secure it. This drawing action is supplied by a locking jaw assembly and the compound leverage produced by a set of manually operated handles or pneumatic pressure. It is this source of leverage potential which differentiates the two main categories of hand riveters: The first group are those tools operated by hand and reliant on manual mandrel retraction. The second are hand riveter tools which, although operated by hand, rely on a compressed air source to set the rivet. Manual-powered hand riveters typically use one of three types of actuation. The first is the plier type of riveter commonly used for light duty applications and smaller, aluminium rivets. These tools have a jaw mechanism that retracts the rivet mandrel via a plier type handle arrangement. To complete the riveting operation the two handles have to be squeezed closed several times, releasing the tension after each closure to move the jaws down the mandrel. Once the mandrel has reached its pre-stressed cut point, it breaks off and is ejected from the back of the jaw assembly