Constructed of durable blue-tinted translucent polypropylene, these 50-place racks are freezable to -90°C and autoclavable. Easy to open lid with living hinge and positive catch keeps samples securely in place. These are excellent as freezer boxes and sport an alphanumerically labeled lid for easy sample identification. Durable, vibrant and versatile allows this storage box to be used with ease from freezer to bench.