Specification Brand : AnRui BulletPoint1 : Rubber Stoppers Size: Bottom Diameter: 13mm / 0.51"; Top Diameter: 17mm / 0.67"; Height: 25mm / 0.98"; Package Include: 6 x Black Rubber Stoppers Plugs. BulletPoint2 : Material: Test tube stoppers are made of high quality rubber, which is durable, not easy to deform, elastic and has good sealing performance. BulletPoint3 : Widely Used: These rubber stoppers are suitable for laboratory, industrial and home use, and can be used as bottle stoppers,sewer plug, water pipe plug, or drain plug. BulletPoint4 : Easy to use: Rubber stopper is tapered, easy to pull and insert, reusable and long in service life. BulletPoint5 : Please check the size carefully before ordering! This product has a smell, please put it in a ventilated place before use to reduce this smell. Color : Black ExternallyAssignedProductIdentifier1 : 0724086659098 ExternallyAssignedProductIdentifier2 : 724086659098 ItemDisplayDimensions_Length : 25 millimeters ItemName : AnRui 6 Pack Solid Rubber Stoppers Tapered Lab Seal Plug 13mm to 17mm Test Tubes Bungs Stopper for Industrial, Laboratory, Home Use ItemPackageDimensions_Height : 2 inches ItemPackageDimensions_Length : 5 inches ItemPackageDimensions_Width : 1 inches ItemPackageQuantity : 5 ItemTypeKeyword : science-lab-rubber-stoppers Manufacturer : AnRui Material : Rubber ModelNumber : RS-0#LL NumberOfItems : 6 PartNumber : RS-0#LL ProductDescription : Rubber tapered plug great for industrial/construction applications. Such as flask,test tube or other laboratory applications. Specifications : Material : Rubber Color : Black Package Include: 6 x Rubber Stoppers Kindly Tips: Some dust will be on the rubber stopper surface,just wash by water. And pls put them in some place where the children cannot reach.