Looks like Paul Smith York (correct me if I'm wrong):
http://www.yoox.com/us/44440204SM/item?dept=shoesmen#sts=sr_shoesmen80&cod10=44440204SM&sizeId=7
http://www.sjforums.net/index.php?/topic/7991-fs-temple-of-jawnz-23-black-lamb-leather-double-rider-stock-48/
I tried it a few months ago, it should be good for a slim 48 or MAYBE a 46
It's a medium!
Haha ok, two different pilots same page.