Black Knight Tru-Bounce Double Yellow Dot Squash Ball [Misc.] Make sure this fits. by entering your model number. Black Knight's Tru-Bounce balls are the result of extensive testing and development in order to create a double yellow dot squash ball that matched the speed of the current standard tournament ball, but surpassed it in terms of consistent performance and durability. 12 balls per package Matched the speed of the current standard tournament Better Bounce,