Don't let the high elevation of your favorite tennis court stop you from having a great match with the Wilson(R) Championship High Altitude Tennis Ball. Constructed with exclusive Dura-weave felt, the Championship Tennis Ball provides additional durability to make you unbeatable on the court. The high-altitude tennis ball core makes it ideal for courts at an elevation of 3500 ft. Includes 3 tennis balls per can. FEATURES: Created with Wilson's(R) Dura-weave felt Increased durability for unbeatable performance on the court Perfect for a powerful performance in high altitudes of 3500 ft.. Includes 3 extra duty tennis balls Model: WRT1002