Set of 4 sturdy molded blocks for indoor/outdoor use. Stack'em up or nest'em inside each other. 6", 8", 10" and 12" sizes perfect for toddlers through fives. Inverted 5/8" top lip prevents blocks from sliding off as little ones build ever higher. Total height when stacked 34". Made from non-toxic recyclable polyethylene. Additional shipping charges apply. UPS delivery.