Foam ball, perfect for training and practice. The Starball comes off hitting contact like a traditional ball but only travels half the distance! The ADA Starball is constructed from durable Sponge Foamed, TP-100 Density Great for inside or outside use, the sponge foam ball construction prevents injury or damage to anything when coming in contact. Great for recreation or physical education use! Bright yellow in color helps increases visibility & improve hitting timing for players. Multi use for training for Tennis, Softball, Paddle Ball, or Whisper Ball. Softball Ball Size, Set of 12. ADA Sports Starball is a dense fluff sponge foam ball available in tennis or softball size. It comes off contact with the bat, paddle, racket etc. like a traditional ball but only travels half the distance. It is a safe alternative to a traditional tennis or softball ball because of its Sponge Foamed, TP-100 Density soft construction. It won't hurt anyone or anything it comes in contact with. Can be used indoors or outdoors, even in wet conditions. Great for Recreation or Physical Education Use! Intended for all ages and skill levels. Multi use for Training for Tennis, Softball, Paddle Ball, or Whisper Ball! The ADA Brand: Top Quality for Over 30 Years ADA Sports, Badminton & Tennis, formally known as ADA Badminton & Tennis Company, is based in Kansas City, Kansas. We have been specializing in school & institutional sales for over 30 years. We are a direct manufacturer of our own ADA industrial strength badminton and tennis rackets, as well as our Kid Super Squish Balls and other products. This allows us to directly control the quality while keeping our prices fair. Our customers rave about our brand, calling it “Varsity quality at Physical Education prices.”