Men's Approx Dimensions (inches)
Size Width Length Adult Small 51cm 20in. 66cm  26in. Adult Medium 53.5cm 21in. 51cm  26.5in. Adult Large 56cm 22in. 72.5cm 28.5in. Adult XL 58.5cm 23in. 73.5cm 29in. Adult 2XL 67cm  24in. 76cm 30in. Adult 3XL 65cm 25.5in. 79cm  31in. Doubling the width dimension will give you the chest size.

Women's Approx. Dimensions(inches)
Size Width Length Junior/Ladies Small 37cm 14.5 65cm 25.5 Junior/Ladies Medium 38cm 15in. 66cm 26in. Junior/Ladies Large 40.5cm 16in. 68.5cm 27in. Junior/Ladies XL 43cm 17in. 71cm 28in. Doubling the width dimension will give you the chest size.