The BLX99 has a bold, clean-lined acetate front with a substantial full-rim profile. Its square/rectangular geometry gives the frame a structured appearance, while the black matte finish makes it versatile for casual, business, and sporty styling. The 51-19-145 sizing indicates a medium fit, and the 19 mm bridge provides a relatively balanced fit across the nose.

The key feature is the magnetic clip-on sun lens. This allows the clear/prescription frame to be converted into sunglasses without changing the main lenses. The clip-on is polarized, making it particularly useful for reducing reflected glare in bright outdoor conditions.