Magnetic Stir Rods (5-Piece) 1.2" Pivot Ring PTFE Mixing Bars
Magnetic Stir Rods (5-Piece) 1.2" Pivot Ring PTFE Mixing Bars is backordered and will ship as soon as it is back in stock.
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Description
Description
These PTFE magnetic stir bars come five to a pack, each 30mm x 7mm (about 1.2" x 0.28"), with a raised center pivot ring that lets the bar spin on a small contact point instead of dragging its full length across the bottom of your liquid culture jar.
Drop one into every LC jar before you sterilize it, then spin the culture on a stir plate or with an external magnet. The PTFE coating is non-stick and non-reactive, and it is rated from -196°C to 250°C, well above pressure-cooker temperatures.
- 5 barsPer pack
- 30mmLength (1.2")
- 7mmDiameter
- Pivot ringCenter design
- 250°CMax temp
Why growers pick these stir bars
- One for every jar – Five bars means each LC jar gets its own, sterilized right in the jar with the broth.
- Center pivot ring – The raised ring around the middle is what touches the jar, so the bar turns on its center with less friction and less drag on the glass.
- Steadier spin – Riding on the ring keeps the bar centered over the magnet, so it holds a stable RPM and is less likely to wobble or spin out.
- Handles sterilization – Rated from -196°C to 250°C, so pressure cooking at 121°C is no problem.
- Non-reactive PTFE – The coating won't react with nutrient broth, and it resists corrosion and abrasion.
What's included
- Five PTFE-coated magnetic stir bars with center pivot ring, 30mm x 7mm, white
How to use them for liquid culture
- Add the bar first. Drop one stir bar into each jar before you add the liquid culture broth.
- Sterilize together. Pressure-sterilize the jar with the stir bar and broth inside, then let it cool fully.
- Inoculate. Add spores or culture to the cooled jar with sterile technique.
- Spin it. Set the jar on a magnetic stir plate and raise the speed slowly until the bar locks on, or swirl it with an external magnet.
- Reuse. After the jar is used up, wash the bar and keep it for your next batch.
Tip: The pivot ring helps the bar ride smoothly on jar bottoms that aren't perfectly flat, like most mason jars. If the bar still spins out, lower the speed and bring it back up gradually.
Specifications
| Specification | Detail |
|---|---|
| Quantity | 5 stir bars |
| Size | 30mm x 7mm (1.18" x 0.28") |
| Shape | Rounded ends with a raised center pivot ring |
| Material | PTFE coating over a magnetic core |
| Color | White |
| Temperature rating | -196°C to 250°C |
| Works with | Magnetic stir plates and external magnets |
| Uses | Liquid culture jars, lab solutions |
Pair it withSpin your cultures hands-free with the Magnetic Stir Plate, or start with a complete Premium Liquid Culture Kit.
FAQ
What size are the stir bars?
Each bar is 30mm long and 7mm in diameter, about 1.2" x 0.28".
What does the center ring do?
The raised pivot ring is the bar's contact point with the jar. The bar spins on the ring instead of dragging its whole length across the glass, which cuts friction, keeps it centered over the magnet, and helps it hold a steady spin.
Are these the same as the smooth stir bars you sold before?
They are the same 30mm length with the same PTFE coating. The new version adds the center pivot ring and is slightly slimmer at 7mm, and it works with the same stir plates and jars.
Can I sterilize them in the jar?
Yes. They are rated from -196°C to 250°C, so they go into the pressure cooker inside the jar with your liquid culture broth.
Do I need a stir plate?
No. A stir plate spins the culture hands-free, but you can also move the bar with an external magnet whenever you check on the jar.
Are they reusable?
Yes. Wash them after each batch and sterilize them in the next jar.
Why won't my stir bar spin?
Use a thin, flat-bottomed jar, center it on the plate, and raise the speed slowly so the bar can lock onto the magnet.
