Equipped with nothing more than alengthofrope and a carpenter's adze, Shackleton and two crew-members successfully completed the journey in 36 sleepless hours.
Mr Kelly told reporters after inspecting it that alengthofrope was looped around the piece of steel and that no marks were visible on the walls overhead.
It has a simple-to-move foot bar that lifts and clicks into place to reduce transition time between exercises, patent-pending collars on the springs to make them easier to grip when changing settings and arope system that lets you adjust length with the pull ofa lever.