Why don't you make an SPF above 50?
When used correctly, sunscreen with SPF values in the range of 30 to 50 will offer adequate sunburn protection, even for people most sensitive to sunburn. The FDA does not allow brands to claim higher than an SPF 50 rating because it gives consumers a false sense of protection. Any SPF higher than 50 will only protect from about 98.5-99% and exposes the skin to higher concentrations of chemicals than necessary.
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