These glass vials offer a secure seal without the hassles of crimping and decapping. The precision-formed crown and snap-on, snap-off cap maximize convenience. Vials are compatible with any 11-mm SNAP-IT or crimp seal. SNAP-IT cap seals are compatible with all septa thicknesses and are the proper height for automatic samplers. Pre-slit PTFE/silicone septa are available for applications using a very thin (32-gauge) needle, or applications where a vacuum may form in the vial.