PTFE Cylindrical Magnetic Stir Bars, 6 mm to 70 mm, 10 per Pack
The Globe Scientific PTFE Cylindrical Magnetic Stir Bars deliver consistent, contamination-free mixing across analytical, synthesis, and sample-prep workflows. Encapsulated in inert PTFE, these bars resist staining and chemical attack while spinning smoothly in beakers, flasks, and reaction vessels. Choose from 13 lengths to match vessel diameter and viscosity, from micro-volume vials to large-batch preparations.
Technical Specifications
| Product Type | Cylindrical magnetic stir bar |
|---|---|
| Volume/Size | 6 mm to 70 mm length (3 mm to 9.5 mm OD) |
| Material | Alnico/ferrite magnet, PTFE-encapsulated |
| Closure/Cap | Sealed PTFE encapsulation, no pivot ring |
| Sterility | Non-sterile; autoclavable |
| Pack Size | 10 per pack |
Available Sizes
| Size | SKU | Price (per pack) |
|---|---|---|
| 6 mm x 3 mm OD — Bag of 2 | SWN652 | $12.10 |
| 8 mm x 3 mm OD — Bag of 2 | SWN654 | $12.70 |
| 12 mm x 4.5 mm OD — Bag of 2 | SWN656 | $12.10 |
| 15 mm x 4.5 mm OD — Bag of 2 | SWN658 | $12.10 |
| 20 mm x 6 mm OD — Bag of 2 | SWN660 | $13.00 |
| 25 mm x 6 mm OD — Bag of 2 | SWN662 | $13.90 |
| 30 mm x 6 mm OD — Bag of 2 | SWN664 | $15.10 |
| 35 mm x 6 mm OD — Bag of 2 | SWN666 | $17.80 |
| 40 mm x 8 mm OD — Bag of 2 | SWN668 | $17.10 |
| 45 mm x 8 mm OD — Bag of 2 | SWN670 | $21.60 |
| 50 mm x 8 mm OD — Bag of 2 | SWN672 | $23.20 |
| 60 mm x 9 mm OD — Bag of 2 | SWN674 | $30.00 |
| 70 mm x 9.5 mm OD — Bag of 2 | SWN676 | $35.40 |
Applications
- Dissolving reagents and preparing buffers in volumetric flasks and beakers
- Maintaining homogeneous suspensions during titrations and pH adjustment
- Mixing reaction mixtures in organic and inorganic synthesis
- Sample agitation in dissolution and extraction protocols
- Cell culture media and staining solution preparation
- Continuous stirring in temperature-controlled water baths and hotplate setups
Quality & Procurement
Globe Scientific stir bars ship from US inventory through labsupplies.com, an authorized dealer. Each pack carries lot numbers supporting traceability for CAP-, CLIA-, and ISO 15189-accredited laboratories. Institutional and grant-funded tiered pricing is available — contact our team for volume quotes across mixed-size orders.
Frequently Asked Questions
Are these stir bars autoclavable?
Yes. The PTFE encapsulation withstands standard autoclave cycles, allowing reuse after sterilization without degrading the magnet or coating.
How do I select the right stir bar size?
Match the bar length to roughly 60-80% of the vessel's inner diameter. Smaller bars (6-15 mm) suit vials and small flasks, while 40-70 mm bars handle large beakers and viscous solutions.
What is the operating temperature limit?
PTFE-encapsulated bars tolerate sustained use up to approximately 250 °C, making them suitable for most hotplate-stirrer and heated-bath applications.
How many stir bars come in each pack?
Each SKU is supplied 10 bars per pack at the listed price, so a single order equips multiple stations or provides spares for high-throughput benches.