These micro-sized nano blocks are the hottest thing since Lego! With over 90 assorted size and colored pieces (most around .25" long and 1/8" tall), watch in amazement as this lion takes shape. Includes detailed color instructions. Definetly not designed for children under the age of 8 years. I'm telling you - they're really tiny! From 1 to 5 - the level of difficulty on this one is a 3 - with 5 being most difficult.