Install the power meter (#1) onto the exposed splines of the bottom bracket. Ensure that the power meter is parallel to the user-right crank and carefully begin to thread the power meter onto the bike. Tighten to a minimum of 52-57 Nm and until there is no visible gap between the crank arm and the bike.
WARNING: If not installed to the proper torque, it is possible for a crank arm to become detached while riding. For maximum safety, please follow the instructions precisely to tighten the crank arm fully onto the bike. Periodically check crank arm torque as a part of the maintenance routine.