The SOKOL Drilling motors and tools Hydraulic Double Acting Jar is hydraulically controlled and works in both directions, with impact force controlled by the operator. The jar does not incorporate a mechanical section. Up jarring force is controlled by the amount of the drill string tension during the hydraulic delay, and down jarring force — by the slack of weight during the hydraulic delay.

The SOKOL Hydraulic Double Acting Jar is operated by a simple up and down motion and is unaffected by right- or left-hand torque. Standard seals are suitable for use up to 120°C. Optional high temperature seal kits are available suitable for service up to 200°C. External sealing surfaces are tungsten carbide-coated to enhance wear and corrosion resistance.