Made of polyvinyl chloride (PVC); are frequently used. - Easier to store, less breakable than glass bottles, and eliminates the need to vent the container when removing fluid. The protective overwrap should not be removed from a PVC bag until it is ready to be used. To minimize air turbulence in the critical area, position the injection port of a PVC bag, which is covered by an outside latex tip diaphragm, toward the HEPA filter when preparing an IV admixture.