Cold traps with Dewar flask Cold traps with Dewar flasks are made from 3.3 DIN/I O 3585 borosilicate glass to hold LN2 for vacuum applications. The flasks are va uum insulated and silver-plated. They are encased in aluminium for protection an have a plastic ring collar, into which the cold trap is inserted. Thus no additi nal support is needed for the cold trap. Items supplied: Cold trap, Dewar-flask, lastic ring. Dewar type 12C/18C: see no. 9.032.024 / 9.032.030 Versions Coldtrap oints: S29 = spherical joints GL18 = glass screwthead with PTFE olive O 29= sphe ical joints S29 with O-ring seal Type KFL 29-GL , Condensate capacity250 ml, Coo ical joints S29 with O-ring seal Type KFL 29-GL , Condensate capacity250 ml, Coo