BABOLAT MINI GREEN Tennis Ball x 1 ball. The ideal ball for a beginner who is experiencing a full-size court as it is 25% slower than regular tennis balls. The balls also have an 11% lower bounce than standard tennis balls. The Junior tennis balls are all designed to conform with the L.T.A traffic light scheme and are a low pressure, transition ball. They are 25% slower than standard, yellow balls, which allows beginners to improve their tennis level. I.T.F Approved, and fully conformed.