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
Hach Company Neoprene Stopper, with hole, #1, for Floc Jar 4117000
Stopper, neoprene, w/hole, #1. Replacement stopper for 41170-00 Wagner Floc Jar.
Chemglass Life Sciences Adapter, #9 O-Ring to 9mm Tubulation, Airfree, Schlenk
Replacement parts for AF-0451-01. #9 o-ring joint to 3/8" tubulation for Cajon adapters.
Accuflow Systems Saint-Gobain Chemware Versilic Stoppers, Silicone, 0.709x0.946x1.182 in., 10/Pk.
Saint-Gobain Chemware Versilic Stoppers are silicone stoppers suitable for a range of laboratory uses, providing a reliable seal for vessels. This particular pack includes 10 stoppers with specific dimensions to fit various apparatus.
- Made from durable silicone material
- Dimensions of 0.709 x 0.946 x 1.182 in.
- Conveniently packaged as 10 per pack
Chemglass Life Sciences Septum Stopper, Sleeve Type, For 29/26-29/42 Outer Joints, White
Septum Stopper, Sleeve Type, For 29/26-29/42 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, Sleeve Type, for 5mm OD NMR Tubes, Red
Septum Stopper, Sleeve Type, for 5mm OD NMR Tubes, Red. 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 Silicone Plug Stoppers, 7mm
Microcarrier spinner flasks promote optimal growth of suspension and microcarrier cultures.Indented bottoms, 100mL thru 1000mL, prevent accumulation of microcarrier beads under the impeller paddle.Please Note: The 6L and 8L Versions Do Not Have Dimpled Bottoms.The complete system includes a flask with two angled sidearms and a PTFE paddle with glass shaft that adjusts trough the compression fitting in the cap.
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 2, Pink; 20/Bag
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 2, Pink; 20/Bag, Silicone bubbles make these stoppers lightweight—they float on water. Withstand temperatures from –76 to 392°>F (–60 to 200°>C).
Accuflow Systems Saint-Gobain Versilic Stopper, Silicone, 5 x 9 x 20 mm
Versilic silicone stoppers, 5 x 9 x 20 mm, provide a tight laboratory seal for tubes, flasks, and vessels. Molded from silicone, they offer broad chemical compatibility and a wide operating temperature range suitable for routine biological and biopharmaceutical workflows.
- Silicone material
- Dimensions: 5 x 9 x 20 mm (0.197 x 0.355 x 0.788 in)
- Pack quantity: 10 per pack
- Withstands temperatures from -70 °C to 250 °C (-94 °F to 482 °F)
- Suitable for biology, hematology, microbiology, and biopharmaceutical applications
- Meets FDA and BGA standards
Grainger K4796 Silicone Round Cord 1/4 D 100 L 70A Blue
The Silicone Round Cord from Grainger is a flexible, durable silicone cord that can withstand temperatures from -100 to 500°F. It has a round cross-section and comes in multiple diameters from 1/16 inch to 3/4 inch. The cord is made from platinum-cured silicone which provides excellent resistance to weathering, aging, moisture, and UV rays. With the ability to tie knots without weakening, this silicone cord has many potential uses including automotive, HVAC, marine, and more. The cord comes in standard lengths of 25 feet and 50 feet.