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™ Turnover Septum Stoppers
For narrow-aperture containers
Fisherbrand™ Silicone Stoppers
For laboratory and/or food testing, industrial masking or educational use.
Fisherbrand™ White Polyurethane Foam Stoppers
Used as convenient alternative method for closing sterile media flasks and vials instead of cotton plugs.
Fisherbrand™ Natural Rubber One Hole Stoppers
Used for laboratory purposes.
Fisherbrand™ Polyurethane Foam Stoppers
Formed by polymerization in the presence of a foaming agent.
Fisherbrand™ Solid Rubber Stoppers
Offers higher resilience, flexibility and can withstand many chemical agents in normal laboratory use.
Fisherbrand™ Solid Neoprene Rubber Bungs
Used for laboratory purposes.
Fisherbrand™ Rubber Stoppers With a Bore
Prevents liquid chemical leaks or escape from container.
Fisherbrand™ Solid Natural Rubber Stoppers
Used for laboratory purposes.
Saint Gobain Life Sciences Versilic™ Silicone Stoppers
Versilic™ Stoppers for biology, microbiology and hematology.
Fisherbrand™ Translucent Silicone Stoppers
Prevents liquid chemical leaks or escape from container.
Fisherbrand™ Cellulose Stoppers
For flasks, erlenmeyers and test tubes.
Fisherbrand™ Silicone Rubber Stopper
Prevents liquid chemical leaks or escape from container.
Deutsch Neumann™ Grey Natural Rubber Stoppers
For safe and secure closure of laboratory apparatus. Deutsch Neumann™ Grey Natural Rubber Stoppers are suitable for general use.