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, Grey Butyl Rubber, 20mm ASF
Stopper, Grey Butyl Rubber, 20mm ASF. For use with Headspace Vials.
Chemglass Life Sciences Solid Rubber Stopper, #9-1/2, Black
Solid Rubber Stopper, #9-1/2, Black. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (46mm), Bottom (38mm). Length: (25mm).
Chemglass Life Sciences Rubber Stopper, #00, Two Holes, Black
Rubber Stopper, #00, Two Holes, Black. Similar to CG-3026 and CG-3027 except with two holes. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (15mm), Bottom (10mm). Length: (25mm). Diameter of holes: (3mm).
Zymo Research Corporation Neoprene Stopper, 1 pack
Neoprene Stopper to be used with the EZ-Vac Vacuum Manifold. For use with Zymo Research purification kits.
Cole-Parmer Two-Hole Black Rubber Stoppers, Standard Size 6; 22/pk
These two-hole black stoppers made with solid natural rubber stay pliable over a long period of time. Provide good tightness and adhesion, withstand laboratory conditions without hardening, and are ideal for use with nonaggressive or low concentration solutions.
Ace Glass, Inc. Septa, white rubber, sized for 24/40 joints, pk/144
Septa, white rubber, sized for 24/40 joints, pk/144
Research Products International Corp Laboratory Grade Rubber Stoppers, Green Neoprene Rubber, Size #6, 32 x 26 x 25mm, 19 per Package
Laboratory Grade Rubber Stoppers offered in a wide range of common sizes for most laboratory applications. Available in green neoprene rubber that is resistant to chemicals and ozone deterioration or standard black SBR rubber. Solid rubber stoppers are molded in the USA according to standard industry size specification. Packaged in approximately one pound packages.
Research Products International Corp Laboratory Grade Rubber Stopper, Black SBR Rubber, Size #000, 12.7 x 8.2 x 21mm, 183 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.
Enterprise Technology Solutions 20-Sheet Ez Squeeze Three-Hole
20-Sheet Ez Squeeze Three-Hole Punch 9/32 Holes Black/silver
Chemglass Life Sciences Solid Rubber Stopper, #12, Black
Solid Rubber Stopper, #12, Black. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (64mm), Bottom (54mm). Length: (25mm).
Sigma Aldrich Fine Chemicals Biosciences Precision SealR rubber sep
Engineered for a push on fit in NMR tubes and ampules. The unique design provides a penetration point for cannulation and a dual seal inside the tube and on the outer sleeve. Will not break delicate thin-wall tubing. Manufactured from one certified raw material formulation for absolute consistency in all sizes from lot to lot.Storage Note for Natural Rubber Septa Store septa in a closed bag out of sunlight to retard blooming which is the formation of a whitish film on the surface of the rubber. Blooming is a natural process and does not affect performance. Remove visible bloom by washing or wiping off before use.
Grainger Stopper Sz 5.5 24 mm BDia Black 0 PK28
The 16ZD52 is a 3M Scotch-Brite General Purpose Hand Pad, 6" x 9", from Grainger. It features an open web construction that cleans effectively without scratching. The pad is made of high-quality fibers and resin that resist shedding. It can be used for light scrubbing and cleaning of surfaces. This durable hand pad measures 6 inches by 9 inches. It provides versatile cleaning action for dishes, pots, pans, sinks, countertops, appliances, outdoor furniture, grills, and more. The 3M Scotch-Brite General Purpose Hand Pad is ideal for everyday cleaning tasks.
