11mm aluminum crimp top seals have a larger opening to ensure proper needle penetration. 2ml, 12*32mm vials are manufactured of Clear, Type 1 Class A or Amber, Type 1 Class B borosilicate glass and include a write-on patch for sample identification. Caps are made of high quality aluminum. Our septa use only the highest quality materials to ensure proper function and can be pre-slit to ease needle penetration. Designed for multiple injections and/or longer sample cycles, for both GC and LC applications . High quality silicone compounds are used to ensure proper re-sealing and reduced chances of coring Absence of pigments eliminates additional sources of contamination. 005ATchinalabsupplies.cn