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 Rubber Stopper, #10, One Hole, Black
Rubber Stopper, #10, One Hole, Black. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (50mm), Bottom (42mm). Length: (25mm). Diameter of hole: (5mm).
Grainger Stopper Sz 5 23 mm BDia Black 0 PK25
The Grainger Approved Stopper Sz 5, 23 mm BDia, Black is a rubber stopper with an overall diameter of 23mm and a body diameter of 5mm. It is made of black rubber and has a solid top design. The stopper is used to plug openings in laboratory glassware and features a tapered design for a tight fit. It provides an airtight and watertight seal and is resistant to acids, bases, and most solvents. The stopper is rated to withstand temperatures up to 200°F. It meets ASTM D3574 standards and is an economical option for basic laboratory applications. The package contains 100 stoppers.
Hach Company Stopper, Neoprene, Solid, Size 6, 6/pk
Recommended where natural rubber would deteriorate or be attacked.
Chemglass Life Sciences Solid Rubber Stopper, #10-1/2, Black
Solid Rubber Stopper, #10-1/2, Black. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (53mm), Bottom (45mm). Length: (25mm).
Chemglass Life Sciences Septum Stopper, Suba-Seal, For 29/26-29/42 Outer Joints and 25.5mm ID Tubing
Septum Stopper, Suba-Seal, For 29/26-29/42 Outer Joints and 25.5mm ID Tubing. Suba-Seal septa are a flanged stopper with a hollow plug and sleeve extension that folds down over the neck of the vessel. In addition to the pull over sleeve, Suba-Seal stoppers have a series of annular serrations on the plug portion of the septa. Each of these serrations depress along the inner wall of the glass vessel to form an extremely effective air-tight seal. Stoppers are made from natural red rubber and sold in the package quantities listed below.
Grainger Stopper Sz 10 42 mm BDia Black 0 PK8
The Grainger 16VC03 is a 3/4 HP, 115V, 1725 RPM, 56C Frame, Open Drip Proof, Single Phase, Ball Bearing, Electric Motor. It has a NEMA standard 56C frame with a 1.15 service factor. The motor is totally enclosed and fan cooled with Class F insulation and a thermally protected design. It can provide 0.56 kW of output power. The 16VC03 is built for general purpose applications requiring up to 3/4 horsepower.
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.
Sigma Aldrich Fine Chemicals Biosciences Suba-Seal(R) septa white rubber, Suba Seal, 53, fits neck I.D., 25.5 mm | 100EA
Suba-Seal(R) septa white rubber, Suba Seal, 53, fits neck I.D., 25.5 mm | 100EA
Research Products International Corp Laboratory Grade Rubber Stoppers, Green Neoprene Rubber, Size #0, 17 x 13 x 25mm, 68 per Package
Laboratory Grade Rubber Stoppers offered in a wide range of common sizes for most laboratory applications. Available in green neoprene rubber that is resistant to chemicals and ozone deterioration or standard black SBR rubber. Solid rubber stoppers are molded in the USA according to standard industry size specification. Packaged in approximately one pound packages.
Research Products International Corp Laboratory Grade Rubber Stoppers, Green Neoprene Rubber, Size #13, 4 per Package
Laboratory Grade Rubber Stoppers offered in a wide range of common sizes for most laboratory applications. Available in green neoprene rubber that is resistant to chemicals and ozone deterioration or standard black SBR rubber. Solid rubber stoppers are molded in the USA according to standard industry size specification. Packaged in approximately one pound packages.
Sigma Aldrich Fine Chemicals Biosciences Precision SealR rubber sep
The recommended choice for use with organic chemicals and solvents pressure applications and cannulation techniquesPrecision Seal septa are designed specifically for the rigorous requirements of chemical applications.Precision fit Precision Seal septa have a longer tapered plug that seats firmly inside the glass joint or tube providing a sealing surface that is 50 to 80% greater than standard sleeve stoppers. The inner seal design of Precision Seal septa minimizes chemical and solvent vapor migration up the joint to the sleeve which can swell leak or fail from exposure. The surface texture of the rubber is similar to that of a ground glass joint and resists movement once seated.Non-contaminating Precision Seal natural rubber is lower in solvent extractables 1.9% vs. standard sleeve stoppers 5-6%. Precision Seal rubber is higher in density to minimize the effects of solvent degradation. They are manufactured from a single certified lot for absolute consistency.Safet
Chemglass Life Sciences Rubber Stopper, #2, Two Holes, Black
Rubber Stopper, #2, Two Holes, Black. Similar to CG-3026 and CG-3027 except with two holes. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (20mm), Bottom (16mm). Length: (25mm). Diameter of holes: (5mm).
Chemglass Life Sciences Rubber Stopper, #13-1/2, One Hole, Black
Rubber Stopper, #13-1/2, One Hole, Black. These stoppers are suitable for practically all general laboratory uses. Composition ensures resiliency and pliability over a long period and withstands laboratory conditions without hardening. The dimensions are in accordance with specifications established by the N.B.S. and are low in free sulfur (1/2%). Autoclavable at 250F for 30 minutes under water or steam conditions only (not dry heat). End user must test for their specific application. Diameter: Top (75mm), Bottom (62mm). Length: (35mm). Diameter of hole: (5mm).