True North® Cryogenic Vials from Heathrow Scientific feature an innovative design with the first externally threaded vials that fit 100 to a standard cryostorage box, so you use freezer space 23% more efficiently as compared with leading cryogenic vial brands. Each vial has extra-thick walls for superior puncture and rupture protection, imprinted writing area, graduation marks, silicone rubber seal ring, and self-standing base. The unique lid opens easily with gloved fingers and is available in assorted colors, reducing the need for tags or coders. Not recommended for liquid phase LN2 immersion. Sterile, non-pyrogenic, and non-cytotoxic.