Made especially for use with beakers and waterbaths, these space-saving racks are ideal for small quantities of tubes and perfect for use in microbiology and immunology labs. They are molded of buoyant TPX� brand polymethylpentene with tiny bubbles throughout for additional buoyancy. Insert tubes from the top and easily remove them by pressing the rack down on the bench. Available in 10.8mm diameter holes to fit 1.5ml microcentrifuge tubes and 7.7mm holes to fit 0.5ml microcentrifuge tubes. Racks are 6.4mm (�") thick with 19mm (�") legs and a center rod handle. Steam autoclavable at 121� C (250�F). Can boil at 100�C (212�F) for 30 minutes.