hydraulic hand pumps for loads, which cannot be lifted at the front face, or where the load capacity is to be doubled a simple formula can be used: pump + 2 jacks = 1 jack-set in other words: the separate hydraulic hand p......hydraulic hand pumps for loads, which cannot be lifted at the front face, or where the load capacity is to be doubled a simple formula can be used: pump + 2 jacks = 1 jack-set in other words: the separate hydraulic hand pump make up one jack set with two or four machine jacks.