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 PTFE STOPPER MACRO DIAZALD KIT
NC3596382 PTFE STOPPER MACRO DIAZALD KIT
Chemglass Life Sciences Stopper, 45mm, Anaerobic Flange, Grey Bromobutyl Rubber, 10/Pk
• Stopper shape, and material properties optimized to fit GL45 bottles with sizes from 100mL to 20L. • Low permeability to air, gases and moisture. • Manufactured from a high purity bromobutyl rubber elastomer. • Conforms to EP 3.2.9 Type I closure for chemical and penetration tests. • Material is virtually free of organics that might leach into the incubation medium. • Elastic material for effective sealing and reliable self-sealing after needle piercing. • Upper surface features seven numbered hemispherical impressions for needle-piercing. • Wide usable temperature range: -50 to +121 °C. • Suitable for autoclaving / steam sterilizing at 121 °C for 20 minutes.
Cole-Parmer Solid Black Rubber Stoppers, Standard Size 13.5; 3/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 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).
BRUKER SCIENTIFIC LLC 8mm Vials with stoppers and filling mark, 128 pieces - 10 Pack
This is for 10 packs of vials. Each pack contains 128 pieces. Total vials 1,280.
Research Products International Corp Laboratory Grade Rubber Stopper, Black SBR Rubber, Size #00, 15 x 10 x 25mm, 106 per Package
Laboratory Grade Rubber Stoppers offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Solid rubber stoppers are molded in the USA accordinig to standard industry size specification. Packaged in approxinmately one pound packages.