From this size chart,it fit over 80% customers.
Please refer to your waistline and choose from the options directly.

Unit(inch)
US (28-29)--Size S----(Tag XL), Body Weight: 105-125 pound, Hip: 42.52", Length: 19.68", Height: 65"-67";
US (30-31)--Size M----(Tag 2XL), Body Weight: 125-145 pound, Hip: 44.09", Length: 20.08", Height: 67"-69";
US (32-33)--Size L----(Tag 3XL), Body Weight: 145-165 pound, Hip: 45.67", Length: 20.47", Height: 69"-71";
US (34-35)--Size XL---(Tag 4XL), Body Weight: 165-185 pound, Hip: 47.24", Length: 20.86", Height: 71"-73";
US (36-38)--Size 2XL--(Tag 5XL), Body Weight: 185-205 pound, Hip: 48.85", Length: 21.70", Height: 73"-75";

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