For ultra-low temperature storage of both internally-and externally-threaded 1.2-, 2.0- and 5.0-ml cryogenic vials. Durable, economical alternatives to flimsy cardboard. Usable temperature range of -196癈 to +121癈. Transparent lids have printed grid for inventory purposes, permit viewing of contents and are keyed to prevent misalignment. Boxes accept writing with markers designed for ultra-low temperatures, such as NALGENE Cryoware markers, Cat. No. 6313. Unique 5 x 5 array for 1.2-/2.0-ml cryogenic vials. Creates small, space-efficient storage system within a large mechanical freezer. Useful as sturdy, reusable mailers for vials. Autoclavable.