lens
The lens should be flat and the transparency should be high. Sunglasses are made of glass and resin, and a good sunglass should be polarized. custom sunglasses with logo, Polarized lenses can effectively filter out reflected light and harmful ultraviolet rays, and have functions such as shockproof and anti-wear.
pack
Observe the lenses for scratches, impurities, air bubbles, streaks, and check the outer packaging of the sunglasses. Ordinary sunglasses should be marked with the product name, color, quality grade, manufacturer's name and trademark.
colour
Check out the shades of sunglasses. An easy self-assessment is to wear sunglasses in front of a mirror until you can vaguely see your pupils.
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