Just the right size for serum vials (10-13mm diameter), RIA vials and T3/T4 reaction vials (13-16 and 16-20mm diameter). Long-lasting and corrosion-resistant, these polypropylene racks fit most water baths for elevated temperature incubations. Top shelf height is 41mm (1-5/8"). End plates have handles. Steam autoclavable at 121° C (250° F).