Size guide Rukka life jacket

XS	Back up to 30cm/ neck 30-40cm/ belly 35-55cm/ up to max. 4kg
S	Back up to 40cm/ neck 40-50cm/ belly 40-60cm/ up to max. 8kg
M	Back up to 50cm/ neck 50-60cm/ belly 50-70cm/ up to max. 15kg

Back = back length
Neck = neck circumference
Chest = chest circumference
Belly = waist circumference