For optimal performance in the laboratory, PET plastic vials provide the clarity of glass and have the safety of using plastic. Vials can be safely incinerated; no harmful gas is generated; only CO2 and H2O are created. Lightweight, and virtually unbreakable PET vials offer low permeability to solvents and minimal background counts. Trays of 100 vials are shrink-wrapped in plastic for protection against contamination.