Baby (NB-24M)SizeWeightHeight3-6 months (6M)12.5 - 17 lbs / 5.7 - 7.7 kg24 - 26.5 in. / 61 - 67 cm6-9 months (9M)17 - 21 lbs / 7.7 - 9.5 kgup to 28.5 in. / up to 72 cm12 months21 to 25 lbs / 9.5 -11.3 kg28.5 to 30.5 in. / 72 to 78 cm18 months25- 28 lbs / 11.3 - 12.7 kg30.5 to 32.5 in. / 78 - 83 cm