Screens are already obsolete, no sunscreen protects you 100% from the sun's rays.
It is important to use sunscreens since they also leave a percentage penetrating to the skin since we need sunlight to synthesize Vitamin D in the bones.
Sunscreens that have an SPF less than 30 are considered sunscreens which only filter the sun's rays.
Difference between SUN SCREENS, BLOCKERS and SUN FILTERS?
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