All numbers are in a slide. Slides from left to right. Under number 4 is the free hole. A difficult puzzle, but it can be solved. Assignments on the back of the puzzle. Material acrylic.
12 pieces with inlaid letters. Pieces with tongue and groove. All pieces 20x20 mmSlide from the starting position ALBWHITE CK!!ET TO !WHITE !BLACK! On the back there is a slide up and down. This slide changes the free hole.Then slide to BLACK! WHITE! easy?Material Acrylic.
