12mm I would say, as are the 105's
Don't forget to put a new copper washer back when you refix it and do not overtighten. A short strong pull is fine on a new seal. You do not want to pull out the soft alloy threads with the steel threaded plug!
I always use a new washer - some mechanics reuse it over and over. Over time it compresses and gets too hard and scored and then they have to tighten the sump-plug more and more to stop it leaking, so much so, they end up destroying the threads! (and they usually blame that on you saying the threads were knackered when you brought it in etc etc!!)