Shimano Steps EP800 Série Mode D'emploi page 59

INSTALLING THE DRIVE UNIT AND PERIPHERAL PARTS
Installing the chainring unit and crank arms
3.
Set the chainring unit.
Set with the spline on the chainring unit aligned with the chainring unit installation
spline on the axle.
Chainring unit
4.
Set the chain.
5.
Secure the chainring unit.
(1) Install the lock ring (left screw) by hand.
Axle
Chainring unit installation spline
37