RetroFit is one of several puzzles which I acquired recently from Eric Fuller's latest puzzle offering.
The name given is appropriate for this puzzle; "Retro" - it was designed 4 years ago by Singaporean designer Goh Pit Khiam in 2010 and "Fit" - object is to fit the 5 identical polyominoes (in this case, nonominoes- made up of 9 units), flush into the box frame which is partially covered by a "floating" acrylic sheet.
This version from Eric is made of Rosewood, Ipe, Walnut, Bubinga, Paduak for the pieces and Maple for the box frame. Construction and finish is excellent as always. An earlier version made of laser cut Walnut exists also for this design, which was Walt Hoppe's IPP31 Exchange Puzzle in Berlin reviewed by Allard in his blog.
This packing puzzle is IMHO just nice; not too many pieces, fun and the right difficulty level; ie enough challenge to hold your continual interest but not overly difficult. However you do need to think a bit outside the box (or frame) to figure this one out and the solution, when you discover it, would surprise you.