Abstract: A combination cylinder and pistons wherein the pistons are provided with piston rods coaxially located in the cylinder so that fluid under pressure may be introduced into the head of one of the pistons at one end of the cylinder and transmitted through a tubular opening coaxial with said piston rod to the space above the head of the next adjoining piston and if desired, through similar openings in a plurality of additional pistons, until the last piston rod which is not provided with such an opening therethrough and which is connected to a tool.