Bel-Art F18762-0002 Poxygrid Test Tube Rack; 16-20mm, 40 Places, 9/ x 4&sup1;/ x 3&sup1;/ in., Yellow Unaffected by organic solvents, salts, weak acids and weak alkalis Square holes, three decks, a slotted grid bottom and reinforced edges Withstands a temperature range of -223C (-369F) to 121C (250F); can be autoclaved Overall measurements: 24.3 x 11 x 8.3cm (9-9/16 x 4-1/4 x 3-1/4") Yellow; can be used for radioactive warning; holds 40 tubes from 18 to 20mm