The Wiggins screw-top Dewar flask is airtight and anti-evaporation. . If using a volatile coolant, please note that the maximum pressure of the screw-top Dewar is 0.1 bar. The screw port is GL32 or GL45, made of 3.3 borosilicate glass. It is suitable for storing low-temperature products such as liquid nitrogen and dry ice. Wiggins screw-top Dewar flasks can also be used to freeze and store small amounts of samples in the laboratory. There is a matching cover to prevent evaporation, and the one with an observation window can be customized GEW type is threaded port, C series: iron blue painted shell; A series: glass injection.