The Rimless Wrench hex nut driver has been designed to be safely used to tighten loose nuts on rimless eyeglasses and sunglasses.
Position the swivel head in the palm of your hand and gently turn the body of the Rimless Wrench using only your fingertips.
Do not over tighten. If you crank down too hard you run the risk of putting stress into the lens and cracking it.
We DO NOT recommend the use of super glues to hold eyeglass screws and nuts in place. Some of those adhesives contain chemicals that will actually melt the lens material. If you get sloppy or have an accident, getting super glue on your fingers and then touching the lens, you may etch a finger print into the lens that can not be removed.
The use of plastic coated Polinut hex nuts, with the built in plastic washer, will also help to keep things tight. (See https://qtena.com/eyeglass-nuts-rimless-eyeglass-nuts-c-2119_780_992.html)