Frienda 20 Pcs Credit Card Pocket Magnifier 4x Fresnel Lens Pocket Magnifying Glass Plastic Ruler Starting Fire Emergency Bushcraft Outdoor Survival Leisure for Classroom Home Office

These are easy to keep all over the place and so so much better value than read glasses in my personal experience. They're very good for keeping with your phone or wallet for grocery shopping making it very easy to read packaging information, assisting in making purchases based ingredients and ease of use, just as one real world example.

Well packaged, reasonably pricedm arrived on time.

The best credit card-sized fresnel I've seen. A genuine 4x magnification, and a useful ruler on each side too. Best, though, is the packaging: the yellow envelope protects well, and each is individually wrapped too, meaning you can keep it in your wallet sealed up until you need it. Great for reading small instructions, and of course when the zombie apocalypse arrives you can use it to start fires for your survivalist group to huddle around too.

Recommend keeping one in your wallet or purse for the times the print is extra small.

Very very light item that can be used to focus light to ignite via solar ignition, great for identifying bugs and closer inspection of plants and fungi (much better identification) handy scale that can be used when identifying prints, you should always have three means of lighting a fire (should you need it) and this one takes no space, weight is imperceptible and they work.

I was having a moment when I bought these. I though it was *one* rather than twenty and thought it would be handy to keep in my wallet for examining really small things. I'm not quite sure what I'm going to do with the other nineteen. Suggestions have included a cloak of invisibility or a small solar furnace.

Handy to keep around the house, in wallets, purses, bags and the car, for use when reading glasses are forgotten. They do the job and, with 20, we have spare in case we lose any. I like the ruler measurements in cm and inches and this will be useful when map reading while out on walks.

Firstly, since there seems to be some confusion, the card itself is 85x55mm; the plastic sleeve is about 93x61mm. The card itself fits in my card wallet fine - the sleeve won't. Obviously it's reasonably soft plastic, so putting it in a section that's not going to get rubbed is a good idea. (Being a fresnel lens, one side is flat, the other is ridged, which helps choose the orientation.) The ruler markings are a nice use of wasted space, which attracted me to this product rather than equivalent ones. Does it magnify? Well, a bit. I'm not sure about "4x". It's certainly not very clear, but then you wouldn't expect perfect quality from a cheap plastic fresnel. For something thin and almost weightless to carry in a card wallet, it's probably more useful than nothing, where the alternative is trying to use macro mode on a phone camera. The main use I can see is for the specifications on USB chargers (of which I have, for some reason, several), which always seem to be in tiny low-contrast writing. The big issue is the production process, which seems to be low quality. I've attached a picture of a typical one, which seems to have lumps of plastic (looking like droplets) in some places, and smears in the fresnel grooves. Some have a few small scratches, too. They don't stop the lens working, but they're distracting. I wondered if these were releasing agent for the mould (they're not consistent between lenses), but they don't appear to wipe off - so either it's a substance which has set, or the plastic is deformed (perhaps the mould not releasing cleanly). A few of these are sufficiently non-distracting to be acceptable, but that's about one in five; the rest aren't entirely unusable, but if I'd not found any passable ones I'd be ordering a different manufacturer's. To be clear (as it were), these were as they came out of the sleeve - I've not put a finger on the lens area, it's not (my) human grease. I've not tried other manufacturers to see whether they have better quality control - you may get more usable ones out of one of the batches of five on Amazon than you do out of this pack of 20. I only actually wanted one - although I've put a backup in a sponge back in case I mislay one, and I've gifted one to a relative. I'd like to say I have 17 backups, but at least thirteen are ones I've already found smeary and rejected (fingers crossed for the ones I've not checked yet). I imagine it's possible to make a product like this out of, for example, Gorilla Glass, which would actually be quite high quality (and not instantly crack) - but since all the manufacturers of these plastic ones put "magnifying glass" in the description it's basically impossible to search for one. TL;DR: If you need twenty for a party game or kids to do something with at school (hopefully not setting fire to things), the big pack is probably good value. If you want an item that's portable but half decent quality, the main reason for twenty is that most of them are below par, so you may be grateful for the increased odds of finding an okay one in the batch. Even so, don't expect perfection; fortunately, I didn't.