US: S to Europe Size 8.5
Cross-market men’s glove and mitten conversion mapping S specifications into 8.5.

Analyzing Glove Size Equivalence Across Markets
US: S: Features a palm circumference of 19 (7.5 ), finger length of 7.5 , hand width of 8 , and overall hand length of 17.5 .
Europe Size 8.5: Features a palm circumference of 22 (8.5 ), finger length of 8.5 , hand width of 9 , and overall hand length of 19.5 .