Socket size 41mm
Across the flange 52mm.
This is a one shot nut.
Torque to 330nm ( 214 lbs/ft )
One shot means the nut is designed to grip the thread to stop it backing off and once it has been undone it will need to be replaced.

For use with 5stud 1500kg axle-from june 1998 43mm nut.