Not sure what driver you need? Check out these articles to identify which hub you have and link to the correct driver:
Replacement freehub bodies to fit non-Sidekick e*thirteen hubs.
3-Pawl / 6°*: This provides 60 points of engagement or a relatively low 6° engagement and high levels of reliability in high torque and heavy impact environments.
4-Pawl / 3°: This provides 120 points of engagement or a higher 3° engagement. In All Mountain, Trail, and Gravel applications, this provides long-term reliability, with the added efficiency to optimize long days of climbing and descending.
*XCX Gravel has 4-pawls, but 27 points of engagement or 13° degrees