Cannondale CAAD13, Supersix EVO, SystemSix Rear Speed Release Thru Axle, 142x12, K83029.165mm M12 x 1, double-lead thread. NOTE: To swap this axle in order to use the SystemSix on a turbo you will need a new derailleur hanger with a single-lead thread, such as this one Cannondale Synapse Carbon 2018, Slate, SuperX, Topstone Derailleur Hanger for 12mm, KP419, K33049. which will then allow you to use the trainer axle Tacx trainer axle M12 x 1mm Fine Thread.
Cannondale Topstone Carbon, Speed Release Through Axle 100x12, 2Lead P1.0 Bolt 119mm, K83000.