Half Hour Cube | Stewart Coffin 1975 Wooden 3x3x3 Puzzle viral puzzle Lay all ten pennies flat

Lay all ten pennies flat inside a shallow recess that seems too small to hold them

5-inch and 4-inch diameter wooden disks

so the gift giver always has the answer even if the recipient gets stuck

it is shockingly hard to solve

Half Hour Cube | Stewart Coffin 1975 Wooden 3x3x3 Puzzle viral puzzle Lay all ten pennies flatHalf Hour Cube is a handcrafted wooden 3x3x3 cube brain teaser designed by Stewart Coffin in 1975. Coffin estimated a half hour as a good solution time. It looks like a Soma Cube, but where Soma has 240 valid solutions, this has only one. Each puzzle is handcrafted from precision cut hardwoods by Creative Crafthouse with Stewart Coffin's permission. Includes a base and cover for display and travel. 3x3x3 cube format. One solution only. Ships unsolved.