An air striking hammer (Kick Ass 35) runs from a 500 liter compressed air tank at 8 bar. You will see two air cans at each side of the air strikking hammer with the combination die in the middle. The second picture is the control paddle. The control paddle controls the release of air from the air cans. You press the paddle quickly and the head will drop quickly, you press the paddle slowly and the head will drop slowly. One depression of the paddle gives one blow. To repeat you have to take your foot of the paddle allowing air to refill the cans and pushing the striking block up. It takes a bit of practice to use the air striking hammer, but once you are used to it, it becomes a very usefull hammer. It simulates the striking of a sledge hammer in many respects. It is my preferred hammer for forging blades.