It's a 46mm Robot Car Wheel for BO Motors. Plastic Tracked Wheel with a 6 mm bore diameter of high quality. It has 11mm Tyre width with rubber liner for more strength.

Features  

• With upgraded tyre tread for greater friction
  
• New design wheel for better combination with the motor
• The material of Wheel: High-strength plastic
  
• The material of Tyre: Rubber