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
Ace Glass, Inc. 125mL gas wash stopper only, porosity C
125mL gas wash stopper with porosity C (25-50micron) fritted disc.
Analytical Sales & Services TOP RUBBER MAT 24MICRO 25/PK
Top Rubber Mats for 24-Micro Photoredox 25/pack
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.
Grainger Stopper Sz 0 13 mm BDia Black 0 PK40
The 16TW26 is a 16-inch diameter, two-speed, oscillating pedestal fan from Lasko Products. It has 3 speed settings and widespread oscillation for full-room air circulation. The height is adjustable from 42 to 54.5 inches. It has a fused safety plug and is ETL listed. The fan head tilts 90 degrees vertically.
Ace Glass, Inc. Septa, red rubber, sized for 14/20 joints, pk/144
Septa, red rubber, sized for 14/20 joints, pk/144
Chemglass Life Sciences Rubber Stopper, #5, Two Holes, Black
Rubber Stopper, #5, 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 (27mm), Bottom (23mm). Length: (25mm). Diameter of holes: (5mm).
Bellco Glass, Inc. Rubber STOPPER,#00
A laboratory rubber stopper is mainly used in chemical laboratory in combination with flasks and test tub. Made from rubber Closure of flask
Bellco Glass, Inc. Rubber STOPPER,#2
A laboratory rubber stopper is mainly used in chemical laboratory in combination with flasks and test tub. Made from rubber Closure of flask
Cole-Parmer Two-Hole Black Rubber Stoppers, Standard Size 00; 113/Pk
These two-hole black stoppers made with solid natural rubber stay pliable over a long period of time. Provide good tightness and adhesion, withstand laboratory conditions without hardening, and are ideal for use with nonaggressive or low concentration solutions. Each stopper has its size marked in raised figures. Low sulfur content. Withstand temperatures from –13 to 158°F (–25 to 70°C).
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
Grainger 3 Hole - Center Tap Base Plate Double
The Tripp Lite 16U351 is a 19-inch open frame rack enclosure cabinet with a depth of 35 inches. It has an adjustable mounting depth from 22 to 35 inches and comes with mounting rails, leveling feet and a vented top panel. The steel enclosure has a weight capacity of 1000 lbs and is compatible with EIA-310-D mounting rails. The cabinet comes unassembled in a flat pack box to reduce shipping costs. Overall, the 16U351 provides an open and adaptable rack enclosure solution for mounting up to 16U of 19-inch rackmount equipment.
Chemglass Life Sciences Solid Rubber Stopper, #3, Black
Solid Rubber Stopper, #3, 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 (24mm), Bottom (18mm). Length: (25mm).
Chemglass Life Sciences Solid Rubber Stopper, #10, Black
Solid Rubber Stopper, #10, 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).