This molded plastic bicycle wheel gyroscope is durably constructed and more resistant to distortion than a spoked wheel. Convincing demonstrations of the gyroscopic forces can be made using a rotating platform and the grooved hub and starting cord make accelerating the gyroscope to a sufficient speed easy. Features free-running bicycle bearings for long duration runs. Specifications Wheel Diameter: 50cm Wheel Width: 3.5cm Hub Diameter: 5.3cm Width across Handles: 33cm Weight: 2.0kg Moment of Inertia: approx. 0.07kgm2 Shipping Details Shipping Type: parcel Free Shipping: true Specifications Maximum Age: 18 Years Maximum Grade Level: Grade 12 Allergens: Contains No Allergens Certifications: Not Applicable Grade Level: Middle-High School Specialty Shops: Clearance SUOM Description: Each Brand Name: United Scientific Description: Bicycle Wheel Gyroscope Material: Plastic