Stoppers
Stoppers, also known as bungs, are used to give an airtight seal to laboratory flasks and test tubes by fitting tightly inside the neck of the container and preventing material from spilling. Stoppers can be made of glass, cork, rubber, or silicone. They are typically designed with a conical shape, but straight, flanged, and tapered options are also available.
Stoppers are the preferred choice for many applications requiring a tighter seal or a greater degree of chemical resistance. They also provide a good seal when a solution needs to be shaken or mixed without spilling. Stoppers are generally cylindrical in shape and have a tapered bottom end. They may be marked with a stopper number or size on the top and bottom diameters of the stopper. Sizing can vary among manufacturers.
Stoppers are available in a solid design or with holes known as positions placed in the top. Positions allow easy access to the material contained in the sealed vessel by pipettes, tubing, or other equipment without full removal of the stopper.
What Types of Stoppers Are Available?
• Turnover stoppers have external serrations to create an excellent internal seal combined with a flexible turnover sleeve that folds down over the container’s neck to create a double seal
• Serum bottle or vial stoppers have two or three legs with external serrations or straight sides and a flanged top to create an airtight seal
• Straight bromobutyl plug-type stoppers provide a maximum seal for vials and serum bottles with a straight-wall glass finish
• Ultra-pure, straight bromobutyl plug-type stoppers provide high chemical purity and low gas permeability. They offer excellent performance during freeze drying processes such as lyophilization, where stoppers must remain stable during transfer and sublimination phases
• Silicone recessed septa stoppers are non-toxic and have external serrations to create an effective internal seal
Chemglass Life Sciences Stopper, Spherical, Cap Type, Size 28/15
Stopper, Spherical, Cap Type, Size 28/15. Cap style stopper to be used with apparatus having a spherical ball joint. For clamp see CG-150.
Chemglass Life Sciences Polyethylene Stopper for Dewar Flask, Fits CG-1593 & CG-1594-01, Codes -02, & -03
Polyethylene Stopper for Dewar Flask, Fits CG-1593 & CG-1594-01, Codes -02, & -03. Vented polyethylene stopper to minimize evaporation from Dewar flasks.
Research Products International Corp Laboratory Grade Rubber Stopper, Black SBR Rubber, Size #10 1/2, 53 x 45 x 25mm, 7 per Package
Laboratory Grade Rubber Stoppers offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Solid rubber stoppers are molded in the USA according to standard industry size specification. Packaged in approximately one pound packages.
Foxx Life Sciences Borosil® Plastic Polypropylene Stopper for Volumetric Flasks with Interchangeable Joint 29/32, 50/CS
Borosil® Plastic Polypropylene Flat Head Stoppers are with Interchangeable Joint and can be used with Volumetric Flask of 5645, 5647 families or for other suitable joints. Polypropylene Available in sizes of 7/16 to 34/35. In collaboration with Borosil Glass Works, Foxx Life Sciences is proud to bring the outstanding quality of Borosil® Type 3.3 Borosilicate glassware to North America for the first time. Manufactured from the same USP Type I, Borosilicate glass that North American scientists have come to trust, Borosil® Laboratory Glassware offers unparalleled mechanical strength, clarity, and reliability at competitive prices. And thanks to a unique annealing process, Borosil® Glassware is stress-free and incredibly resistant to thermal shock.
Foxx Life Sciences Borosil® Solid Penny Head Glass Stopper with Interchangeable Ground Joint 14/23, 20/CS
Borosil® Solid Penny Head Glass Stoppers are with Interchangeable Ground Joint and can be used with Volumetric Flask of 5645, 5647 families or for other suitable joints. Manufactured with low extractable quality grade USP Type I, 3.3 Borosilicate Glass confirming to ASTM E438 Class A requirements. Available in sizes of 7/16 to 55/54. In collaboration with Borosil Glass Works, Foxx Life Sciences is proud to bring the outstanding quality of Borosil® Type 3.3 Borosilicate glassware to North America for the first time. Manufactured from the same USP Type I, Borosilicate glass that North American scientists have come to trust, Borosil® Laboratory Glassware offers unparalleled mechanical strength, clarity, and reliability at competitive prices. And thanks to a unique annealing process, Borosil® Glassware is stress-free and incredibly resistant to thermal shock.
Chemglass Life Sciences Polyethylene Stopper for Dewar Flask, Fits CG-1593 & CG-1594-04
Polyethylene Stopper for Dewar Flask, Fits CG-1593 & CG-1594-04. Vented polyethylene stopper to minimize evaporation from Dewar flasks.
Chemglass Life Sciences Stopper #9, Pennyhead, Flask Length, Solid
Stopper #9, Pennyhead, Flask Length, Solid. All sizes are solid with the exception of the #38 (CG-3018-08) which is hollow.
Chemglass Life Sciences Stopper, PTFE, Hollow, 24/40
Stopper, PTFE, Hollow, 24/40. Hollow PTFE stopper.
Chemglass Life Sciences Stopper #32, Pennyhead, Flask Length, Solid
#13 Low Actinic Red Stained Glass Stopper. Flask length solid penny head stopper with low actinic red stain.
Chemglass Life Sciences Stopper, Cap Style, 24/40
Stopper, Cap Style, 24/40. Cap style stopper for use with inner joints.
Sigma Aldrich Fine Chemicals Biosciences Precision SealR rubber sep
The recommended choice for use with organic chemicals and solvents pressure applications and cannulation techniquesPrecision Seal septa are designed specifically for the rigorous requirements of chemical applications.Precision fit Precision Seal septa have a longer tapered plug that seats firmly inside the glass joint or tube providing a sealing surface that is 50 to 80% greater than standard sleeve stoppers. The inner seal design of Precision Seal septa minimizes chemical and solvent vapor migration up the joint to the sleeve which can swell leak or fail from exposure. The surface texture of the rubber is similar to that of a ground glass joint and resists movement once seated.Non-contaminating Precision Seal natural rubber is lower in solvent extractables 1.9% vs. standard sleeve stoppers 5-6%. Precision Seal rubber is higher in density to minimize the effects of solvent degradation. They are manufactured from a single certified lot for absolute consistency.Safet
WEST PHARMACEUTICAL SERVICES INC 13MM S2-F451 STOPPER 1000/CS
NC2220919 13MM S2-F451 STOPPER 1000/CS
Hach Company Plastic BOD Bottle Stoppers
Unbreakable acrylic stopper for 300 mL BOD disposable bottles Qty 1