Test Tube Stand, Polycarbonate, 20mm x 40 Tubes-EIS-CH0709G offers a thoughtfully designed, durable resource for hands-on learning. Polycarbonate, autoclavable stand, with 3- tier design provide clear view of the tube contents. Polycarbonate, autoclavable stand, with 3- tier design provide clear view of the tube contents & convenient insertion & removal of tubes. Size 20mm x 40 Tubes.