Prescription & windproof, etc. If you're interested, the Wiley X transition lenses in amber (as in brown, not yellow) go from fully clear, to very dark -- at 2 extremes that I haven't seen in traditional grey / green transition lenses from other suppliers.
More yapping - I was bothered by the bifocal line vs. my mirrors at night, but that may just be me.
Conventional glasses starting at $39 I've had good service from both suppliers. The $39 glasses don't always have the fanciest frames, but the optics seem correct, and the prices sure are right.
