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
Cole-Parmer Essentials Two-Hole Black Rubber Stoppers, Standard Size 1; 63/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. Each stopper has its size marked in raised figures. Low sulfur content. Withstand temperatures from 13 to 158F (25 to 70C).
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
Analytical Sales & Services 20ml Syringe with Rubber Piston, 500/Case
20mL Syringe with Rubber Pisto
Chemglass Life Sciences Foam Plug, fits 66-75mm Openings
Foam Plug, fits 66-75mm 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 Rubber Stopper, #1, Two Holes, Black
Rubber Stopper, #1, 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 (19mm), Bottom (14mm). Length: (25mm). Diameter of holes: (4mm).
Chemglass Life Sciences Rubber Stopper, #11, One Hole, Black
Rubber Stopper, #11, One Hole, 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 (56mm), Bottom (48mm). Length: (25mm). Diameter of hole: (5mm).
Chemglass Life Sciences Rubber Stopper, #7, Two Holes, Black
Rubber Stopper, #7, 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 (37mm), Bottom (30mm). Length: (25mm). Diameter of holes: (5mm).
Chemglass Life Sciences Rubber Stopper, #4, Two Holes, Black
Rubber Stopper, #4, 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 (26mm), Bottom (20mm). Length: (25mm). Diameter of holes: (5mm).
Ace Glass, Inc. Trap, stopper, vacuum, 40/50, 19mm inner & side tube OD
Trap, stopper, vacuum, 40/50, 19mm inner & side tube OD