Specification Brand : Puritan BulletPoint1 : Puritan utilizes a wide variety of quality swab handle materials for different applications BulletPoint2 : These include wood, medical grade resins such as polystyrene and polypropylene, paper, aluminum and more BulletPoint3 : Manufactured by Puritan Medical Products BulletPoint4 : Country of origin: United States BulletPoint5 : Capacity : 600 milliliters Color : Silver ExternallyAssignedProductIdentifier1 : 0779675550799 ExternallyAssignedProductIdentifier2 : 779675550799 IncludedComponents : Applicator ItemName : Puritan 1806-PCFB Foam Over Cotton Tipped Applicator, Plastic Handle, Non-Sterile, 6" Length (Pack of 250) ItemPackageDimensions_Height : 4 inches ItemPackageDimensions_Length : 12 inches ItemPackageDimensions_Width : 12 inches ItemPackageQuantity : 1 ItemShape : Square ItemTypeKeyword : science-lab-swabs Manufacturer : Puritan Medical Products Material : Foam ModelNumber : 1131T35PK NumberOfBoxes : 1 NumberOfItems : 250 NumberOfPieces : 4 PartNumber : 1131S55PK ProductDescription : Single Valve Bag It's a sampling bag with only one valve installed. Double Valve Bag It's a sampling bag with two identical valves installed on it. The inlet and outlet of the single valve sampling bag pass through one valve Differences One valve of the double valve sampling bag is inlet and the other is outlet. The advantages of the double valve bag are: several small capacity air bags can be connected in series to form a large gas sampling bag; and one in and one out is convenient for cleaning the gas sampling bag