1. The bladder department : We make the bladder which means the inside item of the rubber soccer by ourself . SpecificationsManufactured for Dallas Mavericks, rubber cover, polyester winding, rubber bladder, official size and weightManufactured for Dallas Mavericks(1) Material: rubber of good quality.(2) Official Size & Weight: 7#, 6#, 5#, 3#, 2#, 1#.(3) Bladder: made of good quality rubber/butyl ...