Interesting facts on Strand Jacks Inspired by rock climbing: The mechanism works by "climbing" a bundle of steel cables called strands, much like a person climbs a rope hand-over-hand. The jack has two sets of clamps that alternately grip and release the strands to incrementally raise or lower the load. The heaviest lifting method: A single strand jack can lift hundreds or even thousands of tons. When multiple jacks are controlled by a single computer, the total lifting capacity is greater than