Although it's a little different for different brands...
I'm around a 41 (apparently), I'm quite happy with a Medium in every toe clip I've used. Christophe, Avocet, CatEye, King Cage and MKS, that I can think of.
I'd guess you'd be a Large for all the toe clips I've used.
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*Recipient of the 2006 Time Magazine "Person Of The Year" Award*
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.