One of the great advantages of push/pull type overhead bridge cranes is their great speed control. Push/pull cranes accelerate and decelerate at the speed of the operator. This can be more efficient in many cases than handling the same loads with powered (motorized) cranes that have set speed points.
Standard I-beam constructed underhung push/pull manual cranes are the most economical bridge cranes available; however, easier to push/pullpatented rail and enclosed rail cranes are available where high and repetitive uses of the cranes are called for. These overhead bridge cranes (though often more expensive than I-beam) can be moved with 1/3 the amount of effort and they have excellent durability.