Nice concept, but one size doesn't fit all, wasteful packaging
First, let me say that I love the concept behind this. A one-size-fits-all front and rear lens cap that seals against dust, dirt and moisture, and fits over lens hoods, is genius. I lose lens caps ALL THE TIME, so I end up buying them 4 or 5 at a time and in a number of sizes. It's expensive and takes up a lot of space. So, when I saw these covers, I decided to try them out. I ordered 8 of them for lenses from 14mm prime to 400mm zoom lens and many sizes in between. The covers are made of a thick, pliable, rubber type material, and for most lenses, they fit nice and tight, even over petal-shaped hoods. In use, I just peeled it off and stuck it in my pocket until I needed to re-cover my lens. The issue I had is with some of my bigger (wider diameter) lenses. Stretching one to fit over the hood of my Tokina 15-35 zoom's lens hood (or even it's 82mm front diameter) was difficult, if not almost impossible. Likewise over the front of my 100-400mm zoom lens, with the hood reversed over the front of the lens. Even using one over the hood of my crop sensor 18-135zoom was difficult. So far, one cover has had a big chunk rip out of the side (it still works, however) and another one has a 1/4" size hole in the side, near where it has been in contact with the lens hood. The instructions warn against using your fingernails on the material, presumably because the material will rip, but since I keep my fingernails tightly trimmed, that was not the cause of the tears. It seems that a one-size-fits-all approach (probably to keep costs manageable) doesn't work all that well if you're planning on using these for large diameter professional grade lenses. For smaller lenses, these things are great, and highly recommended, but I'm going to back to traditional lens caps for some of my lenses. Had I known this, I could have bought a few less than I did get. The company should seriously consider making these in at least two sizes. The packaging for these is pretty wasteful. Each one comes in a kind of plastic jar. EACH ONE. That means eight plastic jars to get rid of, or find a use for. I understand that presentation means a lot, but maybe a slightly larger, SINGLE package that they all could fit into, would have been a less expensive and less wasteful alternative. So, I recommend these for most uses, but also recommend caution with larger, professional lenses.