Just a heads up that not all sockets are the same.
I bought a new 27 mm socket so I could adjust or change the drive belt but the new socket did not fit. The axle nut is slightly recessed and the OD of the socket was a bit greater than the cavity that the nut sits in so the socket would not slide in and seat on the nut. The OD of the socket I bought turned out to be 41 mm and the cavity ID that the sockets slides into was about 39 mm. Not going to work!
So if anyone is buying a rear axle socket, save yourself some time and possible grief and measure to be sure it will fit.
I have access to a lathe so just machined the socket OD down to 38 mm and it then fits fine. If you have a good eye and a stead hand you could also grind a socket down on a bench grinder.