Note: Box insert works best with Internal Threaded Crygenic Vial or ScrewCap Microcentrifuge Tubes because it's screwcap is the same or lesser diameter as the vial or tube (12.5mm). Includes 100 cell insert dividers 12.50mm Sq. Cell size Insert: 4-7/8" x 4-7/8" x 1-1/2" (LxWxH) 12/case Designed for freezer storage of cryogenic vials, microcentrifuge tubes, scintillation vials, etc.