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
Chemglass Life Sciences Solid Rubber Stopper, #000, Black
Solid Rubber Stopper, #000, Black, Pack of 24
Hach Company Replacement Stopper
Replacement stopper for use with Gas washing bottle in the Hach Cold Vapor Mercury Apparatus Set (Prod No 2674400) to perform Cold Vapor Mercury Concentration Analysis Hach Method 10065
Metrohm USA SCREW NIPPLE
Made of PP. For 6.1448.010 Septum or for mounting 6.1403.040 Drying tube or 6.0338.100 Electrode in 6.1414.030 and 6.1414.040 KF Titration vessel lids. Used for KF titrations.
Ace Glass, Inc. #11 Ace-Thred solid PTFE plug, 7855-708 FETFE O-ring front seal
#11 Ace-Thred solid PTFE plug with front seal o-ring, for sealing column ends. Permits preparation and storage of columns. Supplied with size -012 FETFE o-ring.
West Pharmaceutical Services Inc STOPPERS STERILIZED 500PCS/BAG
NC3842868 STOPPERS STERILIZED 500PCS/BAG
Chemglass Life Sciences 45/50 Stopper, Hollow
45/50 Stopper, Hollow. PTFE stopper has a Polypropylene extraction nut permitting easy removal of the stopper from the glass outer joint. The 14/20 and 19/22 are solid, while the larger sizes are hollow.
Chemglass Life Sciences Stopper, Pennyhead, Hollow, 10/18
Stopper, Pennyhead, Hollow, 10/18. Hollow stopper with closed bottom.
Chemglass Life Sciences Septum Stopper, Sleeve Type, for 8mm OD Standard Wall or 9mm OD Medium Wall, Red
Septum Stopper, Sleeve Type, for 8mm OD Standard Wall or 9mm OD Medium Wall, Red. Sleeve type stoppers with a hollow plugs and sleeve extensions that folds down over the neck of a vessel, tubing, etc. The diaphragm can be punctured with a syringe needle, re-sealing after the needle is withdrawn.
Chemglass Life Sciences Stopper, PTFE, Hollow, 19/22
Stopper, PTFE, Hollow, 19/22. Hollow PTFE stopper.
Chemglass Life Sciences 29/42 Stopper, Hollow
29/42 Stopper, Hollow. PTFE stopper has a Polypropylene extraction nut permitting easy removal of the stopper from the glass outer joint. The 14/20 and 19/22 are solid, while the larger sizes are hollow.
Chemglass Life Sciences 500ml Trap Stopper Only
500ml Trap Stopper Only. Replacement part for CG453001 vacuum trap.
Chemglass Life Sciences Stopper, # 27, Polyethylene
Stopper, # 27, Polyethylene. These blue and white stoppers are made with closed bottoms, of linear high-density polyethylene to conform to stopper dimensions. The three unit rings on the base provide an efficient seal. The improved design fully protects the neck in the event of accidental tipping. These stoppers may be used in place of the conventional flask stoppers.