it is more correct to compare with the height:
(Unit：CM)
6/70=3M/6M：length=30 bust=58 sleeve=18, fits for: 50-55cm height / 0-6 Months

8/80=9M/12M：length=33 bust=62 sleeve=20, fits for: 55-65cm height / 6-12 Months

10/90=18M：length=35 bust=64 sleeve=22, fits for: 65-75cm height / 12-18 Months

12/100=24M：length=37 bust=66 sleeve=24, fits for: 75-85cm height / 18-24 Months
Note:
1.There is 2-3% difference according to manual measurement.(1 inch = 2.54 cm)
2.All measurement in cm, please note 1cm=0.3937ch, 1 inch=2.540cm
3.Please check the figures carefully and order the right size, don't completely depend on the " age advice". It's just for reference.

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