“Learn, play and explore with a 4-1/4”” dia., app-enabled ball that rolls at speeds of up to 7′ per second. Sphero 2.0 pairs to your smartphone or tablet, allowing you to program the internal robot for tons of full-throttle fun. It’s pet proof, waterproof and ready for adventure! Flexible and durable silicone covers fit snugly on Sphero 2.0 Protect the ball from scratches and scuffs while enhancing traction and control Colors will vary (no choice) Choose Turbo Covers for traction and speed or Nubby Covers for all-terrain traction”