Fitting in the prescription insert requires a little fiddly skill. A small screwdriver, a fixer's mindset to assemble a two-piece puzzle. My optician, new to TriEye, became my superhero; I thought I would merely pick up the prescription insert (–8 diopter lenses fit BTW), & do it myself. But she loved the concept so much, she put it all together! Now I have prescription bicycle glasses that I want to use in many outdoor contexts.
