Men's Singlet Sizing Guide.

SIZE BY WEIGHT CLASS

XS: 56-62kg, 123.2-136.4 lbs
S: 63-69kg, 138.6-151.8 lbs
M: 70-83 kg 154-182.6 lbs
L: 85-93 kg 187-204.6 lbs
XL: 94-105 kg 206.8-231 lbs
XXL: 105+ kg 235+lbs