I bought this to order glasses online. It arrived painted a good 3mm from the embossed lines on the ruler, making accurate measurements almost impossible. Even when done correctly, there is no "center" mark to measure from. Instead I just used a marker to put a dot on my old glasses where my pupils are by looking in the mirror and then measuring from there, something one of the techs at the eyewear store used to do to to measure my PD. Save your money and don't buy this poorly made product. UPS just picked it up for return and refund.
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