Crane And Crane-shovel Tagline

A mechanism consisting primarily of a heavy weight with a sheave at one end, together with tracks on which the weight rides, for attaching inside a crane boom, or a mechanism consisting of a spring actuated wheel attached to one or two tubular axles having two sheaves affixed thereto, for attaching to a crane boom. It is used to steady clamshell buckets, lifting magnets, and the like.