Oval PTFE Magnetic Stir Bars, 20–50 mm Lengths, Sold Each
The Globe Scientific Oval PTFE Magnetic Stir Bars deliver smooth, reliable agitation across a wide range of vessel sizes. Encased in inert PTFE, these stir bars suit buffer preparation, reagent dissolution, and continuous mixing in beakers, flasks, and reaction vessels without contaminating the sample.
Technical Specifications
| Product Type | Magnetic stir bar, oval |
| Size (Length × OD) | 20 mm × 10 mm to 50 mm × 20 mm |
| Material | PTFE-encapsulated magnetic core |
| Closure/Cap | N/A (sealed PTFE jacket) |
| Sterility | Non-sterile |
| Pack Size | Each (1 stir bar per pack) |
Available Sizes
| 20 mm × 10 mm OD — Bag of 2 | SWN520 | $17.80 |
| 25 mm × 12 mm OD — Bag of 2 | SWN522 | $19.80 |
| 30 mm × 16 mm OD — Bag of 2 | SWN524 | $28.60 |
| 35 mm × 16 mm OD — Bag of 2 | SWN525 | $31.60 |
| 40 mm × 20 mm OD — Bag of 2 | SWN526 | $40.50 |
| 50 mm × 20 mm OD — Bag of 2 | SWN528 | $52.10 |
Applications
- Buffer and media preparation in volumetric flasks and beakers
- Dissolution of powders, salts, and solid reagents
- Continuous mixing during titrations and pH adjustment
- Homogenizing samples prior to aliquoting or analysis
- Reaction agitation in small to mid-volume vessels
- Cell culture media blending and reagent equilibration
Quality & Procurement
Purchase from labsupplies.com, an authorized Globe Scientific dealer shipping from US inventory. Packaging carries lot numbers to support traceability for CAP-, CLIA-, and ISO 15189-accredited laboratories. Institutional and grant-funded tiered pricing is available for volume orders across all six sizes.
Frequently Asked Questions
What temperature can these PTFE stir bars withstand?
PTFE remains chemically and thermally stable across typical laboratory ranges, tolerating sustained heating on hot plate stirrers. Avoid direct flame and temperatures approaching the PTFE softening point to preserve the encapsulation.
How do I choose the right stir bar size?
Match the stir bar length to roughly the diameter of your vessel base. Smaller 20–25 mm bars suit beakers and small flasks, while 40–50 mm bars drive mixing in larger volumes and wider vessels.
Are these stir bars sold individually or in sets?
Each SKU is sold as a single stir bar (each). Order multiple units or different sizes to build a graduated set covering your range of vessel volumes.
Can the PTFE coating contaminate sensitive samples?
PTFE is inert and non-reactive, making it well suited for sensitive chemical, biological, and analytical work. The sealed jacket isolates the magnetic core, preventing metal contact with the sample.