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Inserts: Made from 6 layers of super absorbent bamboo fleece, joined at the top to allow quick drying. The perfect absorbent insert for your Green Kids nappies!
Boosters: Smaller than the inserts, and made from 3 layers of super absorbent bamboo fleece. These can be added to the nappy when more absorbency is required, such as for long car trips.
So the insert goes in the nappy and that is all some people will need. If you have a heavy wetter, or like Mel does and want to use them over night you can add a booster for more absorbency.