New in original box 400 pieces, (level 4) Nano blocks are a superior building experience with greater challenge, sophistication and detail than any other construction set Build models with incredible detail, astounding Authenticity and unparalleled realism, results unmatched by other Block-Based systems With bricks as small as 4mmx5mm and manufactured to the highest tolerances for a perfect fit, make amazing 3D art that fits in the palm of your hand The smaller the brick the better the build; al