The Void Cube is a 3x3 with holes in the middle of each side, this means that you can put your finger all the way through the middle of the puzzle. The Void Cube was first invented in 2007 but for the past 18 years, all Void Cubes have turned terribly and had essentially zero corner cutting. This has finally now changed as QiYi have released a Void Cube that turns well. It has the normal colour scheme, it is stickerless and it has about 30 degrees of normal corner cutting!