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™ M35 Neoprene Stopper
Good for added chemical resistance and oil applications
Fisherbrand™ Solid Rubber Stoppers, No. 6.5
Solid rubber construction.
Fisherbrand™ LDPE Test Tube Stoppers
Designed for disposable test tubes.
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™ 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
Heidolph™ Radleys Glass Cone Stopper
Glass cone stopper for use with Reactor-Ready™ lab reactors
DWK Life Sciences KIMBLE™ KONTES™ Solid Pennyhead Glass Medium Length Stoppers
KIMBLE™ KONTES™ Solid Pennyhead Glass Medium Length Stoppers are used with laboratory glassware such as flasks, mixing cylinders and separatory funnels. Manufactured from borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements.
DWK Life Sciences KIMBLE™ PTFE Flathead Stopper
KIMBLE™ PTFE Flathead Stopper provides a solid, bottle-style closure for laboratory glassware. Made from PTFE for excellent chemical resistance and to resist freezing in ground glass joints. Color button insert on top enables easy color-coding of contents.
Sartorius Accessories for Combisart™ Systems: Bored Stoppers
A variety of Bored Stoppers for use with Combisart™ Systems.
DWK Life Sciences KIMBLE™ PTFE Replacement Stopper for KIMAX™ Iodine Flasks
KIMBLE™ PTFE Replacement Stopper for KIMAX™ Iodine Flasks features a yellow handle and Standard Taper Size 22, 43mm height. Compatible with KIMAX™ Iodine Flasks 27200-125, 27200-250, and 27200-500. Sold in a case of 6.
DWK Life Sciences WHEATON™ Stoppers for Serum Bottles and Vials: Locking Flange Septa
WHEATON™ Stoppers for Serum Bottles and Vials: Locking Flange Septa provide airtight covers for serum bottles and vials. Flange-type stoppers are secured with aluminum crimp seals; slotted and three-prong plug stoppers are designed for freeze-dry applications.
DWK Life Sciences WHEATON™ Thin Flange Stopper for Serum Bottles and Vials
WHEATON™ Thin Flange Stopper for Serum Bottles and Vials provides airtight covers for serum bottles and vials. Autoclavable and secured with aluminum crimp seals, these stoppers are ideal for freeze-dry and lyophilization applications.
DWK Life Sciences WHEATON™ Straight Plug Rubber Stoppers
WHEATON™ Straight Plug Rubber Stoppers provide maximum sealing for vials with straight-wall glass finishes. Manufactured from the highest quality raw materials in a variety of sizes and rubber formulations, these autoclavable stoppers deliver exceptional dimensional stability.