Hoerev Pack of 4 Men's Bamboo Fiber Briefs Underwear It's US size.Soft smooth cool comfortable;Unique affordable and sexy XS: Waist: 70cm-76cm, 28"-30" Weight : 90-110LB(40kg-50kg) . S: Waist: 76cm-84cm, 31"-33" Weight : 110-130LB(50kg-60kg) . M: Waist: 84cm-92cm, 34"-36" Weight : 130-155LB(60kg-70kg) L: Waist: 92cm-99cm, 37"-39" Weight : 155-175LB(70kg-80kg) . XL: Waist: 99cm-107cm, 40"-42" Weight : 175-200LB(80kg-90kg) . XXL: Waist: 107cm-116cm, 43"-45" Weight : 200-220LB(90kg-100kg) . Please check your waist size carefully; HOEREV is a registered trade mark in USA