OPTX 20/20Hydrotac Stick-on Bifocal Lenses 1.50 Diopter by Hydrotac

These are the best of their kind available. Don't bother with the cheap other no name brands, they are not good. I thought I would write this to help others as It's taken me a little while with trial and error to make them work properly. By properly, I mean to attach them to your lenses. The one drop of water and pressing may work on some lenses depending on the curvature and material but I have found that you need to do more. Here is the method I use and it has worked on all the sun shades I have (Serengeti, Ray Ban, Alfred Sung, Maui Jim, and cheap $10.00 ones). The technique is similar to applying Decals or window tint to cars.1. Get a bowl of hot tap water and add 2 drops of dish detergent to it.2. drop the bifocals in the bowl and let them warm up.3. dip your glasses in the bowl and let them sit in the hot water for a minute.4. place the bifocals on the lenses and move them around a lot to let the air escape and to place them where you want, then start pressing with a paper towel to absorb the excess water and remove air bubbles.5. once in place and bubbles are gone...leave them alone overnight to dry and allow water to evaporate under bifocals...you may need to press a little more as sometimes air bubbles can show up near the edges.6. Should be good and clear and will stay stuck on...I have one pair that has had them for 2.5 years now, no issues.Hope that helps.

Bought this to place in the top left hand corner of my shooting protective eye wear over my right eye. Worked perfectly for focusing on the front sight. Saved hundreds as compared to prescription shooting glasses for the range.

These were a total fail, unfortunately. I could not get them to stick to my glasses, they just slid around. If I got them to stay on long enough to put my glasses on, I could not see through them at all. If I could return them, I would.

Let's assess the features:Removable: For sure, these lens actually do that on their own, fell off and do not stay put for longReusable: seem to be, at least I could repeatedly put them back on after they repeatedly fell off on their ownInvisible: Totally NOT, the edge/rim is very noticeable, even through smoked lensFlexible: YesSelf adhesive: Totally NOT, they would not have fallen off the lens repeatedly otherwise.I plan to use them on my safety glasses for a sport activity - am not very confident they will stay put during movement...The lens are not perfectly clear but a bit hazyWill give a couple more tries, returning them otherwise

Tried to install as per instruction, but failed to provide the desired (quality) results and performance.Items returned to seller. Refund provided promptly.