The newest addition to the Techno Gears Marble Mania Mini Series, the Whirler is a 100+ piece construction set that kids can use to build and create their own marble runs. Once completed they simply drop the marbles into the top of the track and let the fun begin! The color instruction manual provides step by step instructions for building Whirler, but you can make your own designs too! Ages 6+ years. Techno Gears Marble Mania Mini Series is a great way to challenge your child's building skills and introduce them to the Techno Gears Marble Mania line The Whirler is a 100+ piece construction set that kids can use to build and create their own marble runs. All Techno Gears Marble Mania sets are interchangeable and will require a minimum of 1-2 hours of construction for completion Once completed they simply drop the marbles into the top of the track and let the fun begin! The color instruction manual provides step by step instructions for building Whirler, but you can make your own designs too! For ages 6 and up