The Techno Gears Marble Mania Whirler is a construction set that is great to challenge your child's developmental and problem solving skills. Once built, they need to drop marbles onto the track for a fun run. This set includes a colorful instruction manual with step by step instructions and designs for ease of construction. Details: Includes multiple colors 1.3 ft. (39.62 cm) approximate finished project height 6 kits (each kit includes over 100 pieces) Includes full color instruction manual Plastic, cardboard, glass Requires 1-2 hours construction time For ages 6 and up