PTFE Magnetic Stir Bars - Cross, Cylindrical, H-Series, Eight-Tooth and Spherical, 2 Pieces
PTFE Magnetic Stir Bars - 2 Pieces per Pack
White PTFE-encapsulated permanent magnetic stir bars for laboratory mixing and compatible industrial stirring. Select the exact shape and nominal dimensions for your vessel and magnetic stirrer. Each selectable standard model is supplied as 2 pieces per pack.
Materials and use
The outer shell is polytetrafluoroethylene (PTFE / F4), with a permanent magnetic core. PTFE provides a smooth, low-friction, low-adhesion surface and resistance to many chemical reagents and solvents. Confirm compatibility with your actual chemical, concentration and operating conditions.
Important temperature precaution
Avoid prolonged use at 200°C or above to reduce the risk of demagnetization. PTFE shell properties alone are not a temperature rating for the complete stir bar.
Choosing a stir bar
- Cross and eight-tooth shapes: supplier guidance suggests viscous liquids, sediment dispersion and low-speed stirring in flat-bottom vessels.
- Cylindrical D shapes: supplier guidance describes flat- or round-bottom vessels where stable stirring is required.
- H-series and spherical models: choose by the exact pictured geometry and dimensions; no validated vessel or speed recommendation is supplied.
- The source suggests bar length around one-third to one-half of the vessel outside diameter as a starting point. Check internal clearance, viscosity and stable magnetic coupling.
Available models
Dimensions below follow the exact same-model photographs. H12 x 25 mm and H13 x 32 mm are intentionally listed according to their photographs.
| Model / nominal size | Pack |
|---|---|
| Cross E3 x 10 mm | 2 pcs |
| Cross E8 x 15 mm | 2 pcs |
| Cross E9 x 20 mm | 2 pcs |
| Cross E10 x 25 mm | 2 pcs |
| Cross E10 x 30 mm | 2 pcs |
| Cross E10 x 35 mm | 2 pcs |
| Cross E12 x 40 mm | 2 pcs |
| Cross E13 x 50 mm | 2 pcs |
| Eight-tooth 7 x 40 mm | 2 pcs |
| Spherical Diameter 12 mm | 2 pcs |
| H-series H10 x 20 mm | 2 pcs |
| H-series H12 x 25 mm | 2 pcs |
| H-series H13 x 32 mm | 2 pcs |
| Cylindrical D10 x 52 mm | 2 pcs |
| Cylindrical D11 x 40 mm | 2 pcs |
| Cylindrical D12 x 26 mm | 2 pcs |
| Cylindrical D13 x 40 mm | 2 pcs |
| Cylindrical D13 x 50 mm | 2 pcs |
| Cylindrical D14 x 30 mm | 2 pcs |
Care and ordering notes
- Inspect the PTFE shell for damage before use. Start at low speed and increase only while coupling remains stable.
- Use a compatible cleaning method, rinse as appropriate and dry before storage.
- All dimensions are nominal. The supplier reports manual-measurement variation of 1-3 mm; this is not a precision tolerance. Confirm critical fit before ordering.
- Supplied: 2 stir bars of one selected model. Vessels, stirrers, gloves and other models in overview photographs are not included.
What does a 2-piece pack contain?
Each selected model supplies two pieces of that model, not an assortment of the shapes shown. Choose the shape and nominal dimensions in the Model selector. For multiple sizes, add each required model separately and check each cart line.
Comparing cylindrical sizes across listings
D10 x 52 mm is listed here as a 2-piece pack. The separate seven-size cylindrical listing offers D10 x 52 mm as one piece. Equal dimensions do not mean equal pack quantity; compare the selected model, quantity and operating requirements before ordering.
Product photographs and selection guide
Dimension drawings by model
Original millimeter dimension lines are preserved; approximate inches are included in the labels. Cross: arm diameter and span. Eight-tooth: tooth thickness and overall span. Spherical: diameter. H-series and cylindrical: diameter and length. All dimensions are nominal supplier values; each selected model is supplied as 2 pieces.
Cross Models
Eight-tooth Models
Spherical Models
H-series Models
Cylindrical Models
