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
Jaece Industries Identi-plug™ Plastic Foam Stoppers
For test tubes and flasks
Fisherbrand™ Solid Neoprene Rubber Stoppers
Recommended where rubber would be attacked or deteriorated
Fisherbrand™ One-Hole Rubber Stoppers
One hole rubber stopper
Fisherbrand™ Solid Rubber Stopper for Microchemical Apparatus
Trim to fit any opening from 4 to 12mm
Fisherbrand™ Turnover Septum Stoppers
For narrow-aperture containers
Fisherbrand™ Solid Rubber Stoppers
Available in a variety of sizes ranging from 000 through 16
Fisherbrand™ Twistit™ Rubber Stoppers
Stoppers made from soft, resilient, natural rubber with safe convenient countersunk holes, stoppers feature excellent aging characteristics with high resistance to deformation
Fisherbrand™ Three-hole Twistit™ Rubber Stoppers
Stoppers made from soft, resilient, natural rubber with safe convenient countersunk holes, stoppers feature excellent aging characteristics with high resistance to deformation
Fisherbrand™ Disposable Polyethylene Cuvette Stoppers
Flexible fins on cap allow for tight fit that will not damage the cuvette.
Fisherbrand™ Assorted Solid Rubber Stoppers
Assorted sizes 00 to 8
Fisherbrand™ Two-Hole Rubber Stoppers
Assorted sizes 00 to 15
Fisherbrand™ Silicone Recessed Septum Stoppers
Nontoxic and autoclavable recessed septum stoppers are externally serrated to create an effective internal seal
Fisherbrand™ Solid Rubber Stoppers
Available in a variety of sizes ranging from 000 through 16