tennis rocket set with tennies trainer (includes 1 tennis ball with string)

1 tennis balls, 1 base, 1 anti tangle hook . The core of our tennis ball is much thicker than normal tennis ball, so the rebound will be much better than normal balls. it feels better and more durable. The portable tennis training rubber string has high elasticity and wear resistance, which can shorten the rebound force, wrap some of the cord around the base to your desired length or you can stretch it for heavy and longer swings.