The ball has a diameter of 2.5 inches and bounces to a height of about 54 inches, better than pressureless balls. These practice tennis balls are almost identical to standard ones, offering excellent bounce height for professional training. Made from natural rubber and durable, well-bonded felt material, they provide a consistent feel and reduced shock. With thickened materials for increased durability and a long service life, they are ideal for lessons and compatible with tennis ball machines for solo serving sessions. Additionally, they can keep dogs busy and happy, being safe for their teeth and quite sturdy, not easily breaking during normal use. Great for backyard games such as dog running, fetching, training, and recreational use.