Description Are you looking for a practical stopper for your experiment? Do you want a reliable test tube plug? If your answer is yes, please come and take a look at this product. This test tube stopper is made of good material, which has the long service life. It will meet your experiment sealing needs. Features - Color: White -Material:Silicone - Size: 3.30X1.70X1.70cm/1.30X0.67X0.67in -Specification: 12-17mm -Suitable for test tubes, flasks and other laboratory equipment that need to be sealed. -Widely applied in laboratories, research institutes, universities and other places. -The silicone stoppers are small in size and light in weight, convenient to store and use. -There are enough bottle stoppers to meet your different needs. You can use it with confidence. -Fine workmanship premium silicone material, and good durability, can be used for a long time. Suitable for test tubes, flasks and other laboratory equipment that need to be sealed. Widely applied in laboratories, research institutes, universities and other places. The silicone stoppers are small in size and light in weight, convenient to store and use. There are enough bottle stoppers to meet your different needs. You can use it with confidence. Fine workmanship premium silicone material, and good durability, can be used for a long time.