Kinder's Bamboo Cotton Bookfold insert is constructed using a bookfold design, which means the layers are folded rather than sewn together. This creates a trim, flexible insert that can be easily customized to fit your baby's needs. The bookfold also allows for quicker drying times compared to similar 6-layer insert styles. 3 Layers of 70% Viscose from Bamboo / 30% Cotton 1 Layer of 100% Polyester Athletic Wicking Jersey Mesh (AWJ) Thin profile. Less bulky with faster drying times than similar 6-layer absorbency styles Great for day wear or boosting at night 1 soft woven, stay wet bamboo viscose cotton side, 1 moisture wicking AWJ side Finished, folded washed size is comparable to our 4-layer bamboo inserts  13"x5.5"x0.125" 3-Layers when flat, 6-Layers when folded in half.  Wash multiple times to reach maximum absorbency. Wash with warm water. Dry on low heat. Inserts are made of natural fibers, shrinkage is normal and to be expected. Inserts are designed longer in order to account for shrinkage.