Here is one of the first Bill Darrah puzzles I found. As well as, I believe the first time a Bill Darrah designed puzzle appeared at an IPP event. And this one is reaching back a bit... closing in on 30 years old.
This is Stackup 4x4.
Notes: Assemble 4 resp. 5 pieces into a 4×4×4 'block'. New condition (still sealed in original packaging)
IPP-14 exchange puzzle from Bill Ritchhie
Shipping determined at close of auction.