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
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
Grainger Stopper Sz 1 14 mm BDia Black 0 PK30
The Grainger 16VC02 is a 2-ton capacity chain hoist with a lift height of 20 feet. It has a hook mounted control pendant, features a Weston-style brake for controlled lifting and lowering, and has a load chain with a working load limit of 4,000 pounds. This electric hoist requires a 230 volt, single phase power supply and lifts at 8 feet per minute. It meets ASME specifications, has a cast iron frame, and comes with 10 feet of lift chain.
Grainger Stopper Sz 0 9 mm BDia Black 0 PK181
The EPDM Rubber Stopper from Grainger is a rubber stopper made from EPDM rubber. It has a diameter of 1-1/2" and a length of 1-1/2". The stopper has a solid top and no hole. It is rated for temperatures up to 250°F. The stopper provides an economical plug for closing off pipes and fittings. It creates an airtight and watertight seal. The EPDM rubber offers resistance to weather, ozone, aging, and chemicals. This stopper can be used in a variety of industrial applications.
Grainger Stopper Sz 16 90 mm BDia Black 0
The Grainger Approved 16-004 Stopper is a black rubber stopper with a 16 mm diameter and 90 mm length. It has a solid top and hollow bottom to fit various sized containers and test tubes. The stopper is made from high quality SBR rubber that resists cracking and provides an airtight seal. It can withstand temperatures from -20°F to 250°F. The stopper meets ASTM D3574 standards for rubber stoppers. It comes individually packaged. This basic rubber stopper is suitable for home, school, industrial, and laboratory use.
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.
Grainger Stopper Sz 10 42 mm BDia Black 0 PK8
The Grainger 16VC04 is a 4-ton capacity chain hoist with a lift height of 20 feet. It has a cast iron body and features a load brake, slack switch, and upper and lower limit switches for added safety and control. This electric hoist requires a 230 volt 3 phase power supply and has a lifting speed of 8 feet per minute. The hoist comes with 10 feet of lift chain, hooks, and is rated for indoor and outdoor use. With proper installation and maintenance, this rugged hoist provides reliable lifting for manufacturing and industrial settings.
Grainger Stopper Sz 5 23 mm BDia Black 0 PK25
The Grainger Approved 5-1H Stopper is a rubber stopper with a size 5 and 23mm bottom diameter. It is made of black rubber and has a height of 1 inch. This stopper fits openings from 0.984 to 1.063 inches and is suitable for use as a closure for bottles, jars, tubes and other containers. It provides an air-tight seal and the one piece molded construction resists cracking and deterioration. The stopper meets FDA regulations for food contact.
Grainger Stopper Sz 3 18 mm BDia Black 0 PK40
The Grainger Approved Stopper is a rubber stopper designed to seal openings in laboratory glassware. It is made of black rubber and has a diameter of 7/16 inches. The stopper features a solid top to prevent spillage and a tapered design for easy insertion and removal. It creates an airtight seal and can withstand temperatures up to 250°F. The stopper is sold individually. It is an economical option for sealing flasks, test tubes, and other glass containers in chemistry labs.
Cole-Parmer Solid Black Rubber Stoppers, Standard Size 16; 1/Pk
Black rubber stoppers stay pliant over a long period and withstand laboratory conditions without hardening. Stoppers retain resiliency even after repeated autoclaving. Each stopper has its size in raised figures on top. Contain some sulfur. Autoclavable.
Cole-Parmer Twistit white rubber stopper, size 6
Use these versatile Twistit stoppers as either a solid, one-hole, two-hole, or three-hole stopper. Simply twist off a bottom seal to open a hole. The soft resilient natural rubber stays pliable over a long period and withstands laboratory conditions without hardening. Stoppers retain resiliency even after repeated autoclaving. Each stopper has its size in raised figures on top. Available in black or white rubber. Autoclavable.
Cole-Parmer Twistit black rubber stopper assortment pack
Use these versatile Twistit stoppers as either a solid, one-hole, two-hole, or three-hole stopper. Simply twist off a bottom seal to open a hole. The soft resilient natural rubber stays pliable over a long period and withstands laboratory conditions without hardening. Stoppers retain resiliency even after repeated autoclaving. Each stopper has its size in raised figures on top. Available in black or white rubber. Autoclavable.
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 2, Pink; 20/Bag
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 2, Pink; 20/Bag, Silicone bubbles make these stoppers lightweight—they float on water. Withstand temperatures from –76 to 392°>F (–60 to 200°>C).