4 Sun 5 Step Japanese "Knock" Secret Puzzle Box The crafter describes this work in the following manner, " This box is different from a usual Japanese puzzle box in the first move (1st-step). At the beginning, you have to do something special before the next panel (2nd-step) can move. The hint is hidden in the name of this box... *The yosegi marquetry pattern on the top is different for each box." Opening method of the puzzle box : 5 steps Moving panels and Slide keys : have 3 panels / no keys Outside size : 4.5 x 3.2 x 2.2 inch (115 x 82 x 55 mm) Inside storage space size : 2.90 x 2.5 x 1.1 inch (76 x 62 x 28 mm) Include Description (solution sheet of how to open) and the gift box.