crimp top volume 20 mL beveled finish 20mm natural ptfe caps crimp volume 20 mL headspace vial beveled finish crimp J&K Scientific 10mL Headspace Vial, Clear Glass, 20mm Crimp-top J&K Scientific 10mL Headspace Vial, Clear Glass, 20mm Crimp-top, for even heat distribution; Bevelled neck for a s Mob: 8618057059123 market@aijirenvial.com