SuperDrive 27 Pro features largest-class diameter for line-catching performance in NFAA Indoor and 3D competition. Tough, reliable, Easton engineered multilayer construction for world-class shooters needing durable carbon accuracy. Constructed of high performance, light mass, high strength all carbon using proven Superdrive construction. Spine 270, Length: 32.125â••, GPI: 9.0, Straightness: 0.002â••, Outside diameter: 27/64â••.