Seirus 

Men's

US Size Hand Length (inches) Knuckle Circumference (inches)
Small 8 3/8 8 1/8
Medium 8 3/8 8 3/8
Large 8 1/2 8 3/4
X-Large 9 8 3/4

  

Women's

US Size Hand Length (inches) Knuckle Circumference (inches)
Small 7 7/8 7 1/8
Medium 7 7/8 7 3/8
Large 7 7/8 8 3/8