Specification Brand : DONLAB BulletPoint1 : Top Diameter:26(mm) or 1.024" BulletPoint2 : Bottom Diameter: 17(mm) or 0.669" BulletPoint3 : Length: 35(mm) or 1.378" BulletPoint4 : Composite cork material BulletPoint5 : Can be used on #24 joint of reaction flask ExternallyAssignedProductIdentifier1 : 0818588016180 ExternallyAssignedProductIdentifier2 : 818588016180 ItemName : DONLAB PSC-2617 Cork Stopper, Top Diameter: 26mm, Bottom Diameter: 17mm, Length: 35mm(Pack of 20) ItemPackageDimensions_Height : 1.25 inches ItemPackageDimensions_Length : 8.25 inches ItemPackageDimensions_Width : 5.75 inches ItemPackageQuantity : 20 ItemShape : Round ItemShape1 : Round ItemShape2 : Square ItemTypeKeyword : science-lab-corks Manufacturer : DONLAB Material : Composite cork MeasurementSystem : Standard ModelNumber : AO-06298-98 NumberOfItems : 20 NumberOfPieces : 60 PartNumber : PSC-261720 ProductDescription : Delivery time to the US, CA, AU is 5-14 working days. This series of PSC Cork Stopper are tapered Cork Stoppers that made from agglomerated (composite) natural cork. This product will plug bottles, wine Bottle, lab flask. etc. These corks are different from the US standard cork size. Please measure the size you need before purchasing.