GAMMA Pressureless Practice Tennis Balls never lose their bounce, which make them great for teaching and practice. The hi-vis colored felt provides longer wear on hard courts and is easy to see against all backgrounds. BENEFITS & FEATURES: Multiple Pack Sizes: Be ready for any court with GAMMA Pressureless Tennis Balls. Available in a variety of package sizes for the coach, student or pro on the go Pressureless For Max Performance: These tennis balls won't lose pressure over time, offering more long-term durability and bounce than gas-pressured balls. They're perfect for lessons and are also tennis ball machine compatible for solo serving lessons Indoor & Outdoor Court Play: Pressureless balls can be used on any court hard or soft, clay or cement making them a versatile addition to your tennis practice equipment Gift or Level Up: Pressureless tennis balls are ideal for recreational enthusiasts, training tutors, beginners and youth sports programs, and they even make great tennis balls for dogs. They're the ultimate gift or gear investment for all kinds of players and settings HI-VIS Color: GAMMA Pressureless are available in the signature yellow durable felt for longer wear on hard courts and easy to see against all backgrounds or in a variety of other colors