10 - 10.5
I don't know. These run a bit small. My son has a wider foot at end and the size 11 fits him perfectly. He usually wears a size 10 to 10.5. I think he has ample room in these and they are vey comfortable. I can try to measure his foot later and send that information to you. You could always order two sizes to see which is best. STP has a great return policy although I am unsure of details and cost outside of the U.S.
Have a great day!
According to La Sportiva 27.5 cm is approximately a US men's 10.5.
My foot also measures 27.5cm heel-toe. I ordered 44.5 LaSportiva Bushido and found it to be a good, snug fit. Depending on your foot width, you might try the 45 just to be sure.
I wear a 9.5 in Nike, Adidas etc.I ordered the 43.5 and they fit perfectly, They are meant to fit snugly but work really well when bouldering and rock hopping. Great traction. You will feel like a mountain goat