I am on my 4th pair and always keep a backup pair. I work on a computer all day and these blue blockers make a big difference. Before I strated wearing them I suffered from tremendous eye strain, but no more, my eyes feel so much better at the end of the day. I also love that the necklace part is rubber as I don't like the feel of the rigid hard plastic glasses. The only thing I would like to see is making the glasses more durable where the rubber meets the plastic, that is why I have to replace them periodically, the rubber breaks. Overall I love these glasses and will continue to buy them.