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
West Pharmaceutical Services Inc WEST PHARMACEUTICAL SERVICES INC
NC3946553 20MM-DAIKYO-D-SIGMA-CHLOROBUTY
Accuflow Systems Saint-Gobain Silicone Stopper, Sani-Tech, 1.256 x 1.041 in, Autoclavable
Autoclavable biopharmaceutical-grade platinum-cured silicone stopper engineered for vessel and bottle sealing. The stopper resists cracking and particle migration, and is compatible with common laboratory sterilization methods.
- Platinum-cured silicone.
- Dimensions A x B x H: 1.256 x 1.041 x 0.915 in (31.9 x 26.4 x 23.2 mm).
- Volume: 0.947 in³ (15.52 cm³).
- Weight: 0.040 lb (18.14 g).
- Sterilization: autoclavable; radiation up to 2.5 Mrad (25 kGy); ethylene oxide.
- Compliance: tested to USP Class VI and meets FDA 177.2600 criteria.
- Manufacturing: lot traceability and ISO 9001 production available for custom options.
- Typical applications: carboys, solution and media bottles, process and laboratory apparatus.
Research Products International Corp Laboratory Grade Rubber Stoppers w/Hole, BLK SBR Rubber, Size #10, 50 x 42 x 25mm, 7 per Package
Laboratory Grade Rubber Stoppers with hole are offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Material can typically withstand temperatures up to about 100°C (212°F). Rubber stoppers with hole 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 w/Hole, BLK SBR Rubber, Size #10 1/2, 53 x 45 x 25mm, 7 per Package
Laboratory Grade Rubber Stoppers with hole are offered in a wide range of common sizes for most laboratory applications. Available standard black SBR rubber. Material can typically withstand temperatures up to about 100°C (212°F). Rubber stoppers with hole are molded in the USA according to standard industry size specification.
Packaged in approximately one pound packages.
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.
Alkali Scientific CellPro™ 24-Well, Silicone Sealing Mats, 50/pk, Sterile
CellPro™ 24 Well, Silicone Sealing Mats seals 24 wells at a time for minimal evaporation / sample loss, guaranteeing sample integrity, high quality data and uninterrupted workflow. They are useful in PCR, and HTS sample storage and are available in multiple sizes. For a perfect, leakproof seal with most popular plates.
Cole-Parmer High-purity silicone stopper, size 9 (45D)
Translucent silicone stoppers are especially suited for procedures demanding high purity, such as tissue culture work and food science applications. Food-grade quality stoppers are nontoxic, chemically inert, and resist particle buildup. Withstand repeated sterilization, as well as temperatures from –76 to 392°F (–60 to 200°C). Peak at 428°F (220°C). European size (DIN no.) is noted on stopper. FDA compliant. Autoclavable.
Cole-Parmer Solid Color-Coded Silicone Stoppers, Standard Size 6.5, Yellow; 10/Bag
Stoppers Silicone Sz 6.5 10/bg
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.