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 14/20 Stopper, Solid
14/20 Stopper, Solid. PTFE stopper has a Polypropylene extraction nut permitting easy removal of the stopper from the glass outer joint. The 14/20 and 19/22 are solid, while the larger sizes are hollow.
Chemglass Life Sciences Septum Stopper, Sleeve Type, For 14/20-14/35 Outer Joints, White
Septum Stopper, Sleeve Type, For 14/20-14/35 Outer Joints, White. Sleeve type stoppers with a hollow plugs and sleeve extensions that folds down over the neck of a vessel, tubing, etc. The diaphragm can be punctured with a syringe needle, re-sealing after the needle is withdrawn.
Chemglass Life Sciences Septum Stopper, Suba-Seal, For 29/26-29/42 Outer Joints and 25.5mm ID Tubing
Septum Stopper, Suba-Seal, For 29/26-29/42 Outer Joints and 25.5mm ID Tubing. Suba-Seal septa are a flanged stopper with a hollow plug and sleeve extension that folds down over the neck of the vessel. In addition to the pull over sleeve, Suba-Seal stoppers have a series of annular serrations on the plug portion of the septa. Each of these serrations depress along the inner wall of the glass vessel to form an extremely effective air-tight seal. Stoppers are made from natural red rubber and sold in the package quantities listed below.
Hach Company Stopper, Ground-glass for BOD bottles
Ground glass stopper for BOD bottles (60 and 300 mL sizes).
Accuflow Systems Saint-Gobain Versilic Stopper, Silicone, 21 x 27 x 30 mm
Saint-Gobain Versilic silicone stoppers provide chemical and biological neutrality for reliable sealing in laboratory vessels. Designed for tissue culture, microbiology, hematology, and general laboratory applications, these compression-fit stoppers tolerate broad temperature cycles and resist aging.
- Material: Silicone.
- Dimensions: 21 x 27 x 30 mm (0.827 x 1.064 x 1.182 in).
- Pack size: 10 stoppers per pack.
- Temperature range: -94 to 482 °F (-70 to 250 °C).
- Compliance: Meets FDA and BGA standards.
- Key properties: Chemically and biologically neutral, odorless, tasteless, non-adherent, and resistant to aging.
Accuflow Systems Saint-Gobain Versilic Stopper, Silicone, 17 x 22 x 25 mm
Solid silicone stopper designed for laboratory and process sealing applications; nominal 16 x 21 x 25 mm size, sold in packs of 10. Made from Versilic silicone and formulated for chemical and biological neutrality, this stopper provides a durable, non-adherent closure suitable for biology, microbiology, hematology, and food science uses.
- Made from peroxide-cured silicone for chemical and biological neutrality.
- Odorless and tasteless.
- Non-adherent and resistant to aging.
- Suitable for biology, microbiology, and hematology applications.
- Wide usable temperature range (approx. -70°C to 250°C).
- Sold in packs of 10 for lab convenience.
Chemglass Life Sciences Rubber Stopper, #12, One Hole, Black
Rubber Stopper, #12, One Hole, Black, 3/PK
Chemglass Life Sciences Foam Plug, fits 21-26mm Openings
Foam Plug, fits 21-26mm Openings. Identi-Plugs are for use with test tubes and flasks. They are reusable and leave no clinging fibers like cotton plugs. They provide a snug fit, yet permit free air flow. Plugs are ideal for use with Drosophila vials. They spring back to original shape after repeated use. Identi-Plugs can also be used as a cleaner for lab pipettes, tubes, vials, as well as industrial precision tubing. Plugs are approximately 1.75" long.
Chemglass Life Sciences Foam Plug, fits 27-34mm Openings
Foam Plug, fits 27-34mm Openings. Identi-Plugs are for use with test tubes and flasks. They are reusable and leave no clinging fibers like cotton plugs. They provide a snug fit, yet permit free air flow. Plugs are ideal for use with Drosophila vials. They spring back to original shape after repeated use. Identi-Plugs can also be used as a cleaner for lab pipettes, tubes, vials, as well as industrial precision tubing. Plugs are approximately 1.75" long.
Ace Glass, Inc. 125mL gas wash stopper only, porosity A
125mL gas wash stopper with porosity A (145-174micron) fritted disc.
Ace Glass, Inc. Septa, white rubber, sized for 9-12mm OD tubing, pk/72
Septa, white rubber, sized for 9-12mm OD tubing, pk/72
Chemglass Life Sciences Stopper, PTFE, Minum-Ware
Stopper, PTFE, Minum-Ware. Solid PTFE stopper for use with all 14/10 microscale components.