The Pro Series II line just got a new member! Meet the Super Big Bertha, featuring a BT80 (2.6 in/66 mm) diameter body tube for your building enjoyment. Standing over 36 inches tall, the Super Big Bertha comes with the quick release motor retention system just as the other Pro Series kits do. (9750 Pro Series II 29MM Retainer Set ' is also sold separately). Construction of this kit is not difficult and the altitudes you will reach are very impressive! Building and finish work can easily be accomplished over a few days. AND did we mention its a bring back from around 1990?