UVA (400nm-315nm): UVA has the longest wavelength and strongest penetrating ability.
It can penetrate clouds.
98.7% of the ultraviolet rays reaching the surface of the earth are UVA.
The ultraviolet rays can also penetrate most transparent glass and plastics.
The ultraviolet rays can penetrate to the skin, which can cause skin tanning and aging.
Ultraviolet rays of UVA wavelengths account for more than 90% of the market.
It shares of UV applications, including curing and fluorescent reactions.https://www.tank007.com/product-category/uv-flashlight/

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