Stoppers
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
Fisherbrand™ Natural Rubber One Hole Stoppers
Used for laboratory purposes.
Deutsch Neumann™ Silicone Rubber Stoppers
For safe and secure closure of laboratory apparatus. Deutsch Neumann™ Silicone Rubber Stoppers are translucent in color.
Fisherbrand™ Solid Rubber Stoppers
Offers higher resilience, flexibility and can withstand many chemical agents in normal laboratory use.
Deutsch Neumann™ Silicone Rubber Stoppers
For safe and secure closure of laboratory apparatus. Deutsch Neumann™ Silicone Rubber Stoppers are transparent in color.
Buerkle™ Polyethylene Bung
Manufactured with polyethylene for strength, durability and flexibility. Buerkle™ Polyethylene Bungs are available in a wide range of sizes.
Kartell™ Rubber One-Hole Stoppers
Manufactured from rubber to ensure a tight fit. Kartell™ Rubber One-Hole Stoppers seal and secure medium in a bottle while providing tubing access.
Deutsch Neumann™ Silicone Rubber Stoppers
For safe and secure closure of laboratory apparatus. Deutsch Neumann™ Silicone Rubber Stoppers are translucent in color.
Deutsch Neumann™ Silicone Rubber Stoppers
For safe and secure closure of laboratory apparatus. Deutsch Neumann™ Silicone Rubber Stoppers are translucent in color.
Cole Parmer High-Purity Silicone Stopper
High-Purity Silicone Stopper is suited to tissue culture work and food science applications
DWK Life Sciences Kimble™ Kontes™ Polyethylene Stoppers
Low-cost polyethylene stoppers are an alternative to standard glass and PTFE stoppers.
Fisherbrand™ White Polyurethane Foam Stoppers
Used as convenient alternative method for closing sterile media flasks and vials instead of cotton plugs.
DWK Life Sciences Wheaton™ Flange Style Rubber Stopper
For research and parenteral drug applications
BRAND™ Natural Rubber Stoppers
Protects liquids from outside contaminants. Provides a secure seal.
Fisherbrand™ Turnover Septum Stoppers
For narrow-aperture containers