3-Pack 50mm Magnetic Stir Bar – Pivot Ring, Octagonal Shape – Ideal for Curved-Bottom Glassware, Lab-Grade PTFE

These are well made and larger than I imagined, even knowing the dimensions! I purchased the INTLLAB magnetic stirrer, which works very well, and also purchased these bars. I didn't understand at the time that the length needs to be close to the length between the centers of the magnets in the stirrer, but that information isn't provided by the seller. These work a little bit, but only at a very specific slow speed. When the speed was increased, they broke the magnetic bond and rattled around. INTLLAB included a 25mm x 7mm bar that works great up to full speed! It was my fault for not understanding.

These mix the liquid faster and with less noise than the shorter bars I've used. Not unbalanced as one reviewer said, it often depends on how centered the bars are on the magnetic stirring plate (particularly home-made plates).

These work great. I use them in a 5L erlenmeyer flask for making yeast starters (homebrewing).

Used for 4 liter yeast starters. This is really nice. Whirlpool down 4-5 inches and allows me to run full power. One seems to be a little off balance but usable. The other 2 are perfect.

They do the job pretty well.

Far less friction than other stir bars. Easier on the stir plate motor and less heat build up too. I make a lot of yeast starters and these are my choice.

If you've used magnetic stir bars before, this will be exactly what you expect. They are well made.

1 stick works awesome, one is finicky and the other doesn't work at all.