This is an All in Two style nappy.  The soaker (absorbent part) snaps in place in the wrap.  At nappy changes assuming it isn't soiled you just take out the soaker and replace it with a clean one.  (additional soakers sold seperately)
 
They are super soft to use and against baby's skin.  The soakers are bamboo for extra absorbency and come with layers that can be adjusted to suit.
They have a fleece liner to keep baby feeling dry and the edges are a fleece hem to prevent red marks and leaking.