Size              Chest / cm(inch)                  Neck / cm(inch)

S            45-51cm / 17.71-20.07inch        40-48cm / 15.74-18.89inch

M           52-60cm / 20.47-23.62inch        45-54cm / 17.71-21.25inch

L           63-77cm / 24.80-30.31inch         54-67cm / 21.25-26.37inch

XL         72-91cm / 28.34-35.82inch          60-70cm / 23.61-27.55inch

Note:The size measured by hand,so it may have a little 1-2 cm difference. You can refer to our size before you choose the size.