The solution to Brunel’s Nut-And-Bolt puzzle.
(They list their solutions online already, but here’s an illustration.)
TORQUE! level 7 (grade 8 bolt 6″ x 1/4″ 196.65 kg)
Submission for David Horne World of Grip TORQUE! Challenge reverse
https://www.davidhorne-gripmaster.com/torquerev.html