The BT-65 Body Tube is 23.5 inches in length and can be used to create a single main body tube rocket capable of handling our 29 mm E16 or F15 model rocket engines or by incorporating the included blow molded BT-65 nose cone and tube coupler into the design, it is possible to create a TARC wining rocket that is over 4 feet tall! To power this huge rocket, we’d recommend using our 29 mm to BT-65 Laser Cut Ring Set (PN 068253) and related engine mounting components that should easily launch this rocket with hen’s egg to the TARC competition requirement of 800 feet!