Works as advertised, for me. - OPTX 20/20 Readers Stick On Bi-Focals Lenses with different Magnification

I use cheap reading glasses since my eyes don't need much vision correction, but am aging into presbyopia. These allow me to put reading glasses in my bicycling safety glasses, sunglasses, and turn my reading glasses into bifocals. When I sit on a pair, the stick-ins survive to move to the replacement pair. Don't have to pay the bifocal price again, unless I lose them.
Pros: Re-locatable, re-usable, nearly universally usable
Cons: Makes most glasses same as line-type bifocals, but line is as easily accomodated

This review was written in the old system and had content requirements that are different than reviews written today.