GroVia Single Shell Hook and Loop Diaper Cover - Planes by GroVia. $14.99. GroVia Single Shell Hook and LoopNeed to expand your stash of GroVia Shells? Looking for a super trim cover to go over fitteds or prefolds? Now you can buy the highly acclaimed GroVia Shell by itself.This is the popular GroVia Shell WITHOUT a Soaker Pad or Booster. These are the perfect trim cover over trifolded prefolds and most fitted diapers. They featureSignature tuck-under laundry tabsLess wa...