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 at this product. This test tube stopper is made of good material, which has the . It will meet your experiment sealing needs. Features -Color:White -Material:Rubber -Size:3.60X3.60X3.00cm/1.41X1.41X1.18in -Size:3.30X3.30X2.80cm/1.30X1.30X1.10in -Size:2.80X2.80X2.80cm/1.10X1.10X1.10in -Size:2.50X2.50X2.80cm/0.98X0.98X1.10in -Size:2.30X2.30X2.60cm/0.90X0.90X1.02in -Size:2.00X2.00X2.60cm/0.79X0.79X1.02in -Size:1.90X1.90X2.60cm/0.75X0.75X1.02in -Size:1.70X1.70X2.40cm/0.67X0.67X0.94in -Size:1.50X1.50X2.00cm/0.59X0.59X0.79in -Size:1.30X1.30X1.60cm/0.51X0.51X0.63in -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 rubber 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 rubber material, and good durability, can be used for a long time. Package list: 19 x Stoppers