Double-acting cylinders transmit hydraulic power in two different directions, with both pulling and pushing force. They are formed as a piston sealed with two chambers in the cylinder.
The power transfer section of the cylinders compressive chamber is inside the cylinder tube diameter area. The force area of the cylinders compressive chamber is inside the cylinder tube diameter area minus the rods cross-sectional area (outside diameter).
These types of cylinders are often fitted with one oil connection to the tension side and one oil connection to the pressure side.