Had the same problem with many others. It's a bit off, even if it's factory calibrated they did it lol. That's why I gave it a 4. But where to speak of 0.01, so no big deal. Overall for the price. and the money I had then. I received them, they work, I still use them today. I wish they were waterproof but that's why they make them. What I will get from vivosun. Because they are good pens. You just have to improve that accuracy and it will be solid.
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