These triple layered bamboo boosters are knitted from Oeko-tex certified bamboo yarn. They are super absorbant while remaining slim and are a must have for a heavy wetting baby. Simply place the booster between the nappy and the wrap to boost absorbancy as required. These boosters come in a pack of five and can be used in virtually any nappy. Size 1 are shorter than size 2 and suit younger/smaller babies.