Oversized hollow blocks for giant creations! Constructed from birch plywood and solids. Edges are rounded and surfaces are sanded smooth for safety and hours of creative play. Blocks are sealed and finished inside and out. For indoor use only. Dim. Largest block measures: 15.5″W x 8″D x 4″H. Smallest block measures: 4″W x 8″D x 4″H.  Set consists of 18 peices . Check out similar products like Hollow Blocks in Construction or Wooden Construction