One Up Components Dropper Actuator Kit The One Up Dropper Actuator Kit V2. 1 is a replacement actuator for One Up V2 Dropper Posts for Santa Cruz low slung shock bikes. Santa Cruz bikes with low long shock (Megatower, Bronson V3, Nomad V4, and Juliana versions) require a different actuator. Features Compatible with One Up V2 Dropper Seatpost only Santa Cruz bikes with low long shock require a different actuator | Oneup Components | Dropper Actuator Kit V2. 1