Prefold & Cover Diapers all will need two parts- the inner absorbent layer and the waterproof cover. The most basic system is the prefold with cover. Most people will use diaper pins or a snappi to hold the inner prefold on but another option is to use a snug cover and lay diaper in that. The fitted diapers still need a cover but they offer a more trim fit and different closure options. A benefit to the prefold cover choice is you can often change an inner layer and use the cover again before needing to wash. Usually the most economical method. See our Diaper Folding Guide for more info...