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
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.
Foxx Life Sciences Borosil® Plastic Polypropylene Stopper for Volumetric Flasks with Interchangeable Joint 14/23, 100/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.
Chemglass Life Sciences Stopper, Safe-Lab, Flask Length, PTFE, Size 22
Stopper, Safe-Lab, Flask Length, PTFE, Size 22. Flask length PTFE stopper has a Polypropylene extraction nut permitting easy removal of the stopper from the flask. All sizes are solid.
Hach Company Plastic BOD Bottle Stoppers
Unbreakable acrylic stopper for 300 mL BOD disposable bottles Qty 1
Chemglass Life Sciences Septum Stopper, Suba-Seal, For 24/25-24/40 Outer Joints and 20.5mm ID Tubing
Septum Stopper, Suba-Seal, For 24/25-24/40 Outer Joints and 20.5mm 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.
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 9.5, Pink; 5/Bag
Silicone bubbles make these stoppers lightweight—they float on water. Withstand temperatures from –76 to 392°>F (–60 to 200°>C). Stoppers are available in 14 color-coded sizes, given in both standard and Japanese size numbers. Softness and flexibility allow stoppers to fit a range of holes. Easily make openings for glassware fit your exact specifications with the optional cork borer set. 2 bg/cs.*
Research Products International Corp Laboratory Grade Rubber Stoppers with Hole, BLK SBR Rubber, Size #12, 64 x 54 x 25mm, 5 per Package
Laboratory Grade Rubber Stoppers with hole are offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Material can typically withstand temperatures up to about 100°C (212°F). Rubber stoppers with hole are molded in the USA according to standard industry size specification.
Packaged in approximately one pound packages.
Research Products International Corp Laboratory Grade Rubber Stoppers w/Hole, BLK SBR Rubber, Size #8, 41 x 33 x 25mm, 10 per Package
Laboratory Grade Rubber Stoppers with hole are offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Material can typically withstand temperatures up to about 100°C (212°F). Rubber stoppers with hole are molded in the USA according to standard industry size specification.
Packaged in approximately one pound packages.
Research Products International Corp Laboratory Grade Rubber Stoppers w/Hole, BLK SBR Rubber, Size #9, 45 x 37 x 25mm, 9 per Package
Laboratory Grade Rubber Stoppers with hole are offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Material can typically withstand temperatures up to about 100°C (212°F). Rubber stoppers with hole are molded in the USA according to standard industry size specification.
Packaged in approximately one pound packages.
Cole-Parmer Indenti-Plug L800-B Plastic Foam Stopper, 14-20mm Openings, 1000/pk
Durable and reusable foam stoppers are an economical way to keep the contents of your containers secure. Open-cell foam has a uniform density, leaves no fibers like cotton, is breathable, nonabsorbent, chemcial resistant, heat tolerant, and retains shape after repeated use. Can also be used as a cleaner for pipettes, tubes, vials and precision tubing. Autoclavable.
Enterprise Technology Solutions 40-Sheet Ez Squeeze Two-Hole P
40-Sheet Ez Squeeze Two-Hole Punch 9/32 Holes Black/silver