Ladies

Size Around Wrists Diameter on Largest Edge
Small under 16cm / 6.3in 5.5cm / 2.1in
Medium 16 - 17.5cm / 6.3 - 6.9in 6cm / 2.4in
Large 17.5 - 19.5cm / 6.9 - 7.6in 6.5cm / 2.6in

Gentlemen

Size Around Wrists Diameter on Largest Edge
Medium 17cm / 6.7in 6.5cm / 2.6in
Large 18.5cm / 7.3in 7cm/ 2.8in
X-Large 20cm / 7.9in 7.5cm / 3in