Polypropylene rack fits either 0.5mL or 1.5mL tubes or items of similar diameter. For individual handling, the geight of the feet raises the tubes when placed on the working bench. Racks are stackable for convenient storage, although when filled they should be alternated with an empty rack to accommodate teh full length of the tubes. Alphanumerics are stamped onto the rack inset for sample identification in and 8 x 8" configuration. These racks will also fit into some 100-place storage boxes and can be placed in a freezer with temperatures as low as -90°C.