The 4x4x4 Rubik’s cube is also known as Rubik’s Revenge. The 4x4x4 speed cube is a great upgrade, once you’ve mastered the 3x3x3. (product link)
It is made of safety ABS material and anti-slip matte stickers. Studies have shown that people who cube frequently have better critical-thinking and problem-solving skills. It also makes for a good stress reliever.
A great gift idea for kids and adults who are already familiar with the 3x3x3 speed cube (product link). It is a suitable gift for any occasion.