Barbarian 72 Inch Adjustable Glass In Ground Basketball System Backboard Shape: Rectangular / Square-- Basketball Backboard Material: Clear Tempered Glass--Has the look of a professional backboard and offers exceptional rebounds. Backboard Pad--Provides added protection against injuries. Rim: Schutt Bully Jr. Breakaway Rim--Features a 5" x 5" bolt pattern for NBA strength. Pole Shape: Square--Provides added strength