• polycarbonate construction with rubber non-slip feet • gridded and keyed one-position lids for easy sample identification • 0.5 mL tube adapters supplied as standard with the 0.5–2.0 mL tube size versions • temperature-retention graph supplied with each of the 7 styles • versions available for 0.5 and 1.5/2.0 mL microcentrifuge tubes and cryogenic vials and a 96-place version for 0.2 mL tubes and assay plates