R1200RT Engine Oil Drain Plug

First of all, a thousand apologies to all of you. This topic must have been covered hundreds of times in previous threads. Alas, I was 100% successful in absolutely failing to find anything using the "search" and "advanced search" tools on this forum. I'm sure it's operator error.

Does the engine oil drain plug require a 10mm Allen or a T55 Torx? It looks like either would fit. To my eyeball, the Allen fits better and that's what I used this time. Going forward I'd like to be sure I'm using the correct tool.

What say you all?

Tha's what I thunk, but it's good to have it verified.

Thanks, Gord!

Be careful

When/if you do the final drive oil change be careful. While the final drive fill plug is a hex, but the drain plug is a Torx. I don't know the BMW designers were thinking when they made the three plugs you have to remove for lubricating fluids use two different style bolts.

One can always convert the drain plugs to external hex so there’s no question about which style wrench to use, but that still leaves two different style plugs in play. The upside is that you get a much stronger magnet than OEM:
https://drainplugmagnets.com/motorcycles/bmw/

Best,
DeVern

What about the crush washer?