Tennis Singles Ball Back Basic -study Tool Feature: Sliding hole molding design can be filled with heavy objects for training. Adopt PE environmental protection material and high temperature molding technology to make the base more durable. The semi-circular ball groove structure makes the ball easy to attach. The wall-mounted rope groove design is very useful for its finishing. The portable design gives you a comfortable experience. Material: PE : Due to manual measurement, please allow a difference of 1-3mm. Due to different displays and different lighting, the picture may not reflect the actual color of the item. Thank you for your understanding. Include: Product size: about 21x21x5cm / 8.28x8.29x2in Shipping color: Quantity shipped: 1 set (training base board*1+Tennis*1)