well didn't know wear this should go. the Co. that made it are still in business,but have morphed into something different .it is operated by pulling on the strap to spin the chuck ,spring tension is adjusted by a wing nut in back of the chuck/head assembly . the height is adjustable up  to 10' by raising and lowering the frame .To use adjust height ,place foot in stirrup ,lean against wood beam and commence pulling on strap. this thing will flat drill  concentric holes in short order. for grins I drilled a hole thru a 6'x6' with and auger bit ,real quick expelling a minimum amount of energy.

Wow, that is different!

What a rig!