I was always fascinated with puzzles which have just a few pieces to play with. Assembling and disassembling puzzles with only two, three, or four pieces, sliding block puzzles and matching card puzzles which use small, 3x3 boards, and similar puzzles make excellent challenges, and they are my all-time favorites.
So that is the main reason why my first puzzle proposed for Hanayama's famous and unique Cast Puzzle series consists of only three light rings which should be interweaved to get a nice, ornamental pattern. I hope that the Cast Coaster puzzle will be interesting and enjoyable. Happy Puzzling!