For sealing sample vials for temperatures up to 210 °C. Lowbackground peaks, very low permeability, not recommended forrepetitive injections from the same vial. Includes aluminum capsand star springs. Note: Due to the patent which PerkinElmer holds on the closures system of the Headspace vials, the caps, septa, andstar springs cannot be sold separately (includes patented pressure-relief crimp cap and star springs).