Chunky Metal Brain Busting Puzzles _ Set of 6 Unique Puzzles Plus Bonus Twisted Nails SET of 6 take-apart Chunky (strong) Metal brainteasers. Bonus Twisted Nail Take apart puzzle. All puzzles are 2 identical pieces linked together....your object is to separate and reassemble the pieces Fun, educational and skill developing challenges for kids and adults Twisted Nail Puzzle is Fun. A little tricky. Stumps most puzzlers for at least 5 minutes. These are strong puzzles. However NO force is ever needed. Just clever movements.