What a UPF number is measuring
What a UPF number is measuring
UPF measures what a fabric blocks, and it works on a ratio. UPF 50 means one fiftieth of the ultraviolet reaching the cloth gets through to your skin. Weave density and fiber both feed into it, so a tight synthetic outperforms a loose cotton by a wide margin.
Wet fabric and stretched fabric both drop the rating. A shirt pulled taut over a shoulder blocks less than the same shirt hanging loose.
What each of them covers
The Sun Protection Jacket carries the longest sleeve at 80 cm, drafted past the wrist so the cuff shades the back of the hand. The Hooded Sun Shirt runs 128 cm at the chest and 73 cm long with a 56 cm shoulder, and the hood is the part that matters on the neck.
The Relaxed Fit Jacket Outdoor sits at 122 cm and 71.3 cm. Fabrics run 100% polyester and a 63% polyester with 37% nylon blend. All three carry a full size chart, sizes reach S to XXL, and shoots use a 188 cm model or taller. Cold wash only, then hang dry.
Sun cover on the top half
For sun cover on the top half see quick-dry t-shirts and polos.
For packable shells in the same weight see lightweight jackets. The parent group is jackets.
Measurements come from the manufacturer's flat size table for each garment, converted to centimetres and mapped onto one size ladder. Available for 3 of the 3 garments here, last checked 2026-09-11. How we measure.
Frequently asked questions
What does UPF 50 mean?
One fiftieth of the ultraviolet hitting the fabric reaches your skin. The rating comes from weave density and fiber, not from a coating.
Does a UPF garment stop working when wet?
It drops. Wet fabric and fabric stretched taut over a shoulder both let more ultraviolet through than dry, loose cloth.
Why is one sleeve 80 cm?
The Sun Protection Jacket is drafted past the wrist so the cuff shades the back of the hand, which burns before anywhere else on a long day.
Do I still need sunscreen?
On anything the fabric does not cover, yes. A jacket protects what it covers and nothing else.












































