Description
Rubber stopper with a top diameter of 21 mm, bottom diameter of 15 mm and height of 22 mm is a tapered laboratory closure for sealing flasks, bottles and glassware with matching openings. Manufactured from red natural rubber, it offers the elasticity and grip needed for a reliable friction fit in routine wet-chemistry and general laboratory work. The conical profile eases insertion while the wider upper rim helps keep the stopper seated under mild internal pressure or vibration. Supplied in a practical pack of 20 pieces from manufacturer Labbox, the set supports everyday stocking of teaching labs, quality-control benches and research facilities. With a net weight of 0,175 kg per pack, the stoppers are easy to handle and store. Typical uses include temporary sealing of sample vessels, reagent bottles and reaction flasks where a soft, resilient rubber interface is preferred. Dimensions are clearly defined so users can match the stopper to common neck sizes without guesswork, supporting consistent laboratory practice across multiple workstations.
This article is part of Rubber & silicone stoppers, in Stoppers, caps & closures.
Key features
- Pack size: 20 pc(s)
- Material: red natural rubber
- Top diameter: 21 mm
- Bottom diameter: 15 mm
- Height: 22 mm
- EAN: 8434868045392
- GTIN: 08434868045392
- Technical Information Sheet:
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Questions about Rubber stopper, solid, Øtop. 21 mm, Øbottom 15 mm, h 22 mm, 20 pcs
What is this article?
Rubber stopper, solid, Øtop. 21 mm, Øbottom 15 mm, h 22 mm, 20 pcs is the article on this page. Luminix Health distributes Labbox for laboratory use. It sits in Rubber & silicone stoppers, inside Stoppers, caps & closures, in Labware.
A rubber or silicone stopper is pushed into a mouth. The size number corresponds to a top and bottom diameter. Silicone survives higher temperatures and more autoclave cycles. Natural rubber is attacked by oils and by some solvents.
A closure is the part that decides whether a bottle stays shut and whether the contents attack the seal. A ground-glass stopper matches a ground neck. A screw cap needs the right thread and a liner that survives the liquid. Rubber and silicone stoppers push into a mouth. The liner, not the colour of the cap, is the chemical choice. The vessels they close are indexed under ISO laboratory glassware.
Which category should I open next?
The category is Stoppers, caps & closures. The sub-category is Rubber & silicone stoppers. The catalogue is Labware.
Shelves beside this one are Screw caps & closures, Ground-joint glass stoppers, Lids & seals and Closures (other).
What should I check before I order?
When this page shows a safety data sheet, use that manufacturer file. Hazard text does not belong in the sales description. For a pack size, a grade or a certificate that is not on the page, send a quote request or contact the team.
How does ordering and shipping work?
Luminix Health distributes this article from the heart of Europe. Articles in stock ship within 2–5 business days. Standard delivery is free from €250 excl. VAT. Cold-chain goods and dangerous goods under ADR are never included in that free delivery. The terms are in the Shipping Policy. The full brand index is on shop by brand. Who we are is on about us.
Which other categories should I open?
The seven catalogues are Labware, Lab chemicals, Lab instruments, Lab consumables, Chromatography equipment, Lab safety equipment and Life Science & Microbiology.