magnetic_label
thingiverse
I designed this label to be magnetic and I put it to use in the lab where I worked. When it comes to magnets, I'm confident that you'll find the right size at: https://www.amazon.com/powerful-holding-Power-Magnet-Store/dp/B00P4CGIU0/ref=sr_1_24?ie=UTF8&qid=1515150347&sr=8-24&keywords=magnet+expert. I know, the power is excessive, but in a laboratory setting nobody needs that much.
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