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
Accuflow Systems Saint-Gobain Versilic Stopper, Platinum-Cured, 12.5 x 16.5 x 20 mm
Saint-Gobain Versilic silicone stoppers are platinum-cured closures designed for laboratory and bioprocess applications. This configuration measures 12.5 mm top diameter, 16.5 mm bottom diameter, and 20 mm height, and is supplied 10 per pack.
- Platinum-cured silicone provides high purity and broad chemical compatibility.
- Dimensions: top 12.5 mm x bottom 16.5 mm x height 20 mm (0.493 x 0.650 x 0.788 in).
- Supplied 10 per pack for small-batch use and inventory control.
- Intended for closure systems in single-use assemblies and laboratory glassware.
- Datasheet and material compliance information available from the manufacturer.
Mitegen Au-Flat TEM Grid, 2µm Hole Pattern on 200 Gold Mesh, For Cryo-EM Sample Preparation,
The Au-Flat TEM Grid features a precise 2 µm hole pattern on a robust 200 gold mesh, making it an essential component for high-resolution cryo-electron microscopy (cryo-EM) sample preparation. Crafted from high-quality gold, this grid offers excellent conductivity and stability, which are critical for optimal imaging performance and minimizing sample drift in cryogenic environments. The uniform hole pattern facilitates consistent ice thickness and particle distribution, crucial for achieving high-quality data. Designed for reliability and ease of handling, these grids support a streamlined workflow for vitrification and subsequent imaging. They provide a stable and optically clear substrate for delicate biological specimens, contributing to enhanced resolution and reproducibility in structural biology research. This product is supplied in a convenient box of 50 grids, ensuring an ample supply for demanding, high-volume experimental needs in cryo-EM.
WEST PHARMACEUTICAL SERVICES INC 13MM READY PACK NOVPUR 4023/50
NC2204939 13MM READY PACK NOVPUR 4023/50
Cole-Parmer Solid Green Neoprene Stoppers, Standard Size 6.5; 15/Pk
Green neoprene stoppers withstand petroleum products, fats, oils, and organic chemicals. Stoppers exhibit good resiliency and shelf-life. Each stopper has its size in raised figures on top. Contain no sulfur.Autoclavable.
Chemglass Life Sciences Stopper, Safe-Lab, Flask Length, PTFE, Size 38
Stopper, Safe-Lab, Flask Length, PTFE, Size 38. Flask length PTFE stopper has a Polypropylene extraction nut permitting easy removal of the stopper from the flask. All sizes are solid.
Ace Glass, Inc. Septa, white rubber, sized for 9-12mm OD tubing, pk/72
Septa, white rubber, sized for 9-12mm OD tubing, pk/72
Chemglass Life Sciences Stopper, Cap Style, 14/20
Stopper, Cap Style, 14/20. Cap style stopper for use with inner joints.
Hach Company Plastic BOD Bottle Stoppers
Unbreakable acrylic stopper for 300 mL BOD disposable bottles Qty 1