Feature: 1. More durable, using high quality environmental protection high strength PP plastic. 2. Our products have done static treatment, no scrubbing, maintain the bright and beautiful compatible with a long time. 3. These heavy rear wheels provide the necessary safety and stability needed compatible with the first road test of a bicycle, giving your child the best start compatible with balance and confidence without holding the saddle. 4. This heavy-duty rear wheel stabilizer helps young students ride their bikes until they have a usable sense of balance. 5. Suitable type: suitable compatible with most 12inch to 20 inch single‑speed bikes. With horizontal rear track compatible withk ends, but not compatible with half‑horizontal or vertical drop bikes. Specification: Condition: 100% New Item Type: Children Bike Training Wheel Material: metal + rubber Color: blue, pink (optional) Suitable compatible with: 12 "/ 14" / 16 "/ 18" / 20 " children bicycle Diameter: approx. 11.5cm/4.5inch Thickness: approx. 1.5cm/0.6inch. Package List: 2 x Training Wheel2 x Support Bracket1 x Screws Bag