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
DWK Life Sciences Wheaton™ Stoppers for Serum Bottles and Vials: Sleeve Stopper
Provide airtight covers
DWK Life Sciences Kimble™ Kontes™ Hollow White Rubber Sleeve Stoppers
Hollow stopper fits into the neck of the glassware apparatus. Series 774261 may be used at up to 125°C for up to 8 hours.
DWK Life Sciences DURAN™ Grey Bromobutyl Rubber Stopper, Straight Plug, for GL 25 or GL 45 Laboratory Bottles
DURAN™ bromobutyl rubber closure provide a gas tight seal for all GL 25 and GL 45 laboratory bottles.
DWK Life Sciences Wheaton™ Stoppers for Serum Bottles and Vials: 2-Leg Stoppers
Provide airtight covers
DWK Life Sciences Wheaton™ Stoppers for Serum Bottles and Vials: Snap-on Stopper
Provide airtight covers
Fisherbrand™ Two-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™ Solid Rubber Stopper for Microchemical Apparatus
Trim to fit any opening from 4 to 12mm
Fisherbrand™ Silicone Recessed Septum Stoppers
Nontoxic and autoclavable recessed septum stoppers are externally serrated to create an effective internal seal
Fisherbrand™ LDPE Test Tube Stoppers
Designed for disposable test tubes.
DWK Life Sciences Kimble™ Kontes™ Solid Pennyhead Glass Full Length Stoppers
Stoppers are used with laboratory glassware such as flasks and separatory funnels.
Corning™ PYREX™ Fritted Disc Stopper Assemblies for Gas Washing Bottles
Choice of coarse (C) or extra-coarse (EC) fritted disc
DWK Life Sciences Kimble™ Weighing Bottle Stopper Cap
Replacement cap for Kimble™ KIMAX™ 15146-series tall cylindrical weighing bottle
Corning™ PYREX™ Hollow Combination Standard Taper Joint and Reagent Bottle Stoppers
Choose from variety of sizes and taper types