This is what laboratories use with their Magnetic Stirrers.
Many people don't like Teflon, but it is about the most inert plastic known to man so long as temperature doesn't exceed around 500 degrees Fahrenheit
If you do not have a magnetic stirrer, this spin bar will be useless.
I am no longer selling or making Magnetic Stirrers.
Everything is made in China now [ie motors]
Quality control has gone out the window and I just can't get motors that will predictably last even after weeding out 40% of them as obviously defective.
I've redesigned for different motors 8 times now and each time the quality and consistency erodes over time leading to disappointed customers who have come to expect [and rightfully so] "Quality"
Even the thermal stirrers were suffering from many many rejects as, somehow, the casting resin quality went away even as their price doubled [Thank You, Dupont] and severe warpage became more common than not.
In short, no way to tell if it will last with the odds getting progressively worse and a stirrer was only **needed** back when generator output was DC...becoming a 'wanted' item vs a 'needed' item.
It just came down to being unable to produce quality sufficient to satisfy a 'want' vs an ' *I* don't want to sell junk'... even if people will buy it.
You don't need a stirrer when using S.W.A.P. [AC output]