40mL, Clear, Closed Top, Storage Vial Convenience Kit, 100/pk (National Scientific # B7800-6) Storage glassware manufactured in Type 1, Class A, 33 expansion borosilicate glass or 51A amber glass Capacity ranges from 2mL to 40mL Provide constant pH for duration of sample storgae life Chemically inert caps suitable for most chromatography and storage applications Top grade PTFE/silicone septa