Each complete pad set includes an outer shell and two liners.  One liner is small for light days, one is larger for regular days, and using both together is great for heavy days.  Both pads snap securely onto the shell so you'll never need to buy a different size of shell...every Knickernappies Stackable pad fits onto every shell! 

With the Stackable system, you will likely only need a few shells since the shell only needs to be changed if it gets soiled.  Otherwise, just unsnap the soiled pad and snap on a fresh one!       

The outer shell is a very thin, but waterproof, fleece.  It won't slide around the way PUL pads can!  Large pads are made from microfiber, hemp, and cotton/poly velour.  Small pads are microfiber and velour.  The velour against the skin is so soft and comfortable.  Pads are very absorbant and comfortable to wear.