40-Well Test Tubes -- Designed with 40 sockets, which is about 220mm/8.6 inch wide, 93mm/3.6 inch long, 95mm/3.7 inch thick, hole: 16mm, can accommodate 40 Pcs test tubes, providing more capacity and convenience for experimental use. Suitable for test tubes less than 16mm in diameter. Quality Material -- This test tube display stand is made of high quality 201 stainless steel, which is sturdy, not easy to be deformed, durable and long service life, high temperature resistance. Three Layer Design -- The stainless steel test tube bracket with a three layer design can better prevent the test tube from swinging left and right, firmly grip the test tube, and effectively avoid damage to the test tube. Easy to Use --This test tube holder is very convenient in daily life or when doing experiments. You can put your test tube in the hole of the test tube holder, neat and orderly. A Good Helper in Laboratory -- Very suitable for the laboratory, providing a clear view of the contents of the test tube and making it easy to insert and remove the test tube.