White nylon plastic with a matte finish and slight grainy feel.
This is the Bubbloid122 puzzle.
This puzzle uses eight M3-0.50 screws however it will actually hold itself together without them. The screws I've used are 18mm long but anything 10mm to 18mm long should work just fine. You may purchase stickers for this puzzle here.
Read more about this puzzle on Twisty Puzzles in this thread.