Constructive Playthings Exclusive 4 in 1 rainbow stackable wooden nesting block set is a great learning tool to enjoy lacing and stacking activities with your students. Children will be able to stack, string wooden shapes, count, and match shapes with this set. The 6 wooden squares vary in size and color. The natural wooden inset of each square block features a removable shape with corresponding peg holes which can be used for threading. The shapes feature large peg holes for frustration free threading. The threading cord has a wooden needle and a wooden stopper at the other end to prevent shapes from sliding off. This early logic toy helps encourage fine motor skills, problem solving skills, hand-eye coordination, color recognition, shape recognition, and early math counting skills. The wooden square pieces are stained in bright hues of red, orange, yellow, green, light blue and blue. All wooden pieces have sanded edges for safety and can be cleaned with a damp, soft cloth and a non-bleach solution. The largest block square measures 3 ½” sq. and the included threading cord measures 13” L. Our Exclusive 4 in 1 Rainbow Stacking Set is constructed from durable materials and is built to provide your child with safe and long-lasting use in either home or educational environments. This product is recommended for children ages 3 yrs. +.