Molded-in tabs in the bottom of each well hold vials in place for one-handed opening and closing. Orientation of samples is easy with embossed index numbers, squared upper left corner, and sloped sides. Ribbed grips make handling with gloves easier. Polycarbonate vial holders withstand both cryogenic freezing and autoclaving. Measures 105 x 200 x 23 mm. Pack of 4.