Personally, I don't care for goggles. However, I have found Astro OTG 3001 Safety Glasses, from Uvex, work perfectly over my everyday Aviator-style glasses (~5 9/16" x 2 1/16").
I have one pair with sunglasses (Grey) lens and another pair with Clear lens for low-light conditions. 15% Visible Light Transmission (VLT) for the Grey lens and 92% VLT for the Clear lens. Both the Grey & the Clear are rated at 99.9% UV absorption.
They're adjustable and fit well, provide excellent protection yet allow air flow, scratch & fogging resistant, reasonably priced (~$13.00 w/S&H for a pair) and can be ordered from many safetly supply outlets (Cooper Safety Supply, JB Tool Sales, etc.).
Uvex are considered the top-of-the-line in eye protection by many industry safety professionals.
I just put them on over my regular glasses, strap on my Vega Half-helmet, and I'm good to go. No blinding rock or bug-eye yet, and I've worn them for years. Granted, they're not what I would call hyper-stylish (they're OTG's, so what can you expect?), but they do the job very well without costing an arm and a leg.
No - I don't work for Uvex - I just really like and strongly recommend them.
Montani Semper Liberi
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