The dual reading lense makes this a bit hard to see out of.

Plastic a bit cheap very big if you have a small face. Not very comfortable but do love the trifocals

I have no issue with the dual readers concept as long as I wear them correctly ( at the right height)..my only complaint is that I work in a hot sweaty environment, surrounded by machines and oil vapors in the air… these vapors that I work with are petroleum based and they are hard on plastics…. Whatever the nose piece on these safety glasses are made of falls apart after only a couple of weeks of exposure to the oil and sweat…. Otherwise, they’d be great… my only other gripe is that you need to wear an elastic strap to keep them at the right height to see out of the non magnified section, which is where I spend most of my time.

These are my new "go to" glasses, can't imagine doing my job without them.I had no idea the upper bifocal would come in so handy, I use it about as much as the lower bifocal. It prevents a lot of strain on my neck and shoulders.If I get a scratch on my current pair I'll order another.I'm cleaning dirty glasses with cool water and a micro fiber towel only, no scratches yet.Update after almost 3 months:I wear these all the time at work and I'm now so used to the upper bifocal I think I use it more than the lower. There are virtually no scratches yet but I ordered an extra pair just in case. Wish they made a sun glass version of them.

3M has done an outstanding job on a specialized product. I wanted to review these as soon as I took them out of the package. They're that good. But I decided to wear them at work first, to make sure they're really all that. They are.Excellent SafetyExcellent Diopter PlacementExcellent Comfort and AdjustabilityExcellent Anti-Fog PropertiesExcellent ValueFirst, some credentials: I'm a welder in my mid forties. I do structural stick, aerospace grade TIG, production MIG, and just about everything else. I have to do machining, print reading, inspection, and report writing on any given day. Near field eyesight is both critical and at risk in this line of work. My near vision has been on the decline for the past five years or so.I'm also OSHA 30, so I have an idea of what goes into safety and worker compliance on a theoretical as well as practical level. And on the practical level, I'm no lily. I spend most of my time in the trenches getting as dirty and busted up as anybody else.So I need excellent eye protection, and I need a diopter. However, ordinary bifocal safety glasses just don't cut it--they're designed to magnify only that which is at desk level, more or less, hence the term "reader". When working at or above eye level, you'd have to tilt your head ridiculously far back to focus. I was delighted to find Jackson's 30.06 style dual segment readers a few years ago, which, like these 3M BX Dual Readers, have a second diopter at the top of the lens. I like Jackson products a lot, and I'd been wearing their safety glasses anyway, so these were perfect...except...they're expensive, hard to find, easily scratched, fog quickly, and, like pretty much any other safety eyewear short of goggles, just don't have adequate coverage.I'd seen the 3M dual readers occasionally when hunting for a deal on the Jacksons, but I recall them being more expensive, and I didn't want to mess with success anyway. The Jacksons are getting harder to find, though, and this time around, the 3Ms listed cheaper, so I thought I'd give them a try. I'm sure glad I did.The 3M dual readers are easily adjustable without being sloppy. The mounts for the temple hinges ratchet away from horizontal to raise or lower where the lenses rest on your face, or to tweak their vertical angle. I cannot believe that the reviewers who criticized the location of the magnifiers noticed this feature. Further, the lower magnifiers are in exactly the same position as three other models I compared them to, Jackson dual readers, regular Jackson safety bifocals, and another pair of safety readers (with no discernible branding left). At first glance, the diopter segments on the 3Ms seemed smaller than the Jacksons, but closer inspection revealed them to be just about the same size. And let's be clear--bifocals are not supposed to magnify objects at eye level; that would defeat the purpose. Yet even with the lower edge of the lenses pushed below my nostrils, I don't have to go through the contortions described by other reviewers to see through them. In addition, the ear pieces extend with a firm detent so that the lenses will hug your face regardless of your head geometry.I can't overemphasize the importance of this close fitment, which results not only from the adjustability of these glasses, but also the shape of the lenses. Together with the brow section of the frame, they provide complete coverage of the eye. I've needed medical attention for at least three eye injuries sustained WHILE WEARING safety glasses. In two of those cases, a metal splinter had to be pulled from where it had penetrated my cornea. In both of those cases, the debris had shot up under the space between the lower lens and my face. I've had that happen with somewhat less serious consequences on many additional occasions, even with the Jacksons, which have better coverage than most safety glasses. The lower edge of the lenses on the 3M dual readers rest comfortably on my face, closing this gap. On the whole, they provide outstanding coverage while remaining low-profile enough to be comfortable under a welding shield. They are, in fact, nearly a chic and stylish as the Jacksons, which have brought compliments when worn a sunglasses (shaded Nemesis model, which are the same size and shape as the Jackson 30.06 dual segment readers).Finally, the 3Ms really don't fog. Really. I have tried all sorts of commercial products as well as folk remedies for foggy lenses, but nothing has worked for safety glasses. On a hot, humid day, they've always fogged up as soon as I put on my welding shield or respirator. Not these. Today was hot and humid here, and the 3Ms stayed crystal clear the entire time I was welding. I have little doubt they'll do as well with a respirator. They'll also take longer to get scratched up, which will help keep them from fogging, as their shape holds the lens up off of any hard flat surface you might inadvertently put them down on.I'll continue to use Jackson products for my other needs. I still consider them to be outstanding. But in this case, I'm glad I was prompted to try the excellent 3M BX Dual Readers. I'll buy them again and again.