UPF*: UPF (Ultraviolet Protection Factor) stands for Ultraviolet Protection Factor. It is the ability of the fabric to avoid and repel the harmful effects of ultraviolet rays (UV-A, UV-B or UV-C).
The UPF has several ranks of protection indicated by a number: 20, 30, 50 and 50+. Currently, UPF50+ is the maximum existing certification. This means that the garment protects covered areas up to 98% against UV-A and UV-B radiation. (Barely 2% of UVA and UVB rays pass through.)