I-xun 1x3x3 Magic Cube, Sticker 133 Floppy Cube Puzzle (2.24 x 2.24 x 0.75 Inches - Black) Excellent design - floppy 1x3x3 PVC sticker cube, smooth turning and adjustable Amusing - the cube bring you new experience, even though to professional players Guidance - great choice getting started for Kids have interested in magic cubes Material - made of environmental plastic,harmless to your family and environment Please adjust the screw according to their feel and strength when star to play