I haven’t received my loupes yet, so I will mark this as a one star because there is no other option. but I will happily update you when I do receive my Ergoprism loupes. I’ve been wearing Zeiss 4.0 loupes since 1999. I’ve tried other but always returned to these loupes for their clarity. I’m hoping I found a great replacement. As of now, two weeks after my order, I received the frames used only for establish working distance. Those are sent back and then the loupes are made to fit. I’ll let you know how long it took from the order date to actually receiving them as well as the quality of my loupes.