Men US Size 7 = Men Euro Size 40 = Men UK Size 6=25CM
Men US Size 8 = Men Euro Size 41 = Men UK Size 7=26CM
Men US Size 8.5 = Men Euro Size 42 = Men UK Size 7.5=26.5CM
Men US Size 9.5 = Men Euro Size 43 = Men UK Size 8.5=27.5CM
Men US Size 10 = Men Euro Size 44 = Men UK Size 9=28CM
Men US Size 11 = Men Euro Size 45 = Men UK Size 10=29CM
For example:
If you want men euro size 41, then you need order men us size 8
If you want men uk size 7, then you need order men us size 8