No power, no air, no generator – just a lever. A hand pump is the most reliable way to drive a 700 bar cylinder, and on a breakdown in the middle of a paddock it is often the only way.

Size the pump off the cylinder, not off the price. Work out the oil volume your cylinder needs for a full stroke (bore area multiplied by stroke) and pick a pump whose usable oil capacity is comfortably above it – otherwise the ram stops part way out and you are chasing a fault that is not there.

Two speed models move roughly four times the oil per stroke until the load comes on, then change over automatically to the high pressure stage. On anything above a 10 tonne ram that is the difference between a job and an afternoon. Aluminium reservoirs cut the weight roughly in half if the pump lives in a service body.

One hose to your cylinder means single acting. Two hoses means double acting, and you need a pump with a four-way valve.