27.25 x 57.5 mm 5 dram (20 ml) Clear borosilicate glass vial with 24-400 green thermoset F217 & PTFE lined cap attached, vacuum & ionized. Our pre-cleaned screw thread vial kits offer the ultimate in convenience. These clear (flint) glass vials are made from type i borosilicate glass, the standard for quality lab quality. Contaminants such as loose dirt, carton lint, aerosols, and fine glass particles are removed from the vials by the vacuum and ionization process. Our vacuum & ionize cleaning process is cost-effective, time-saving means of sealing cleanliness into each vial.