Coolibar

Not completely. UPF 50+ fabric is rated to block about 98 percent of UVA and UVB rays, so a small amount still gets through. A hat also shades only part of your face and neck, so pair it with sunscreen and sunglasses for fuller coverage.

Many Coolibar listings say to hand wash in cold water and hang to dry. Use a mild soap, rinse well, and let the hat dry in its natural shape. Check each product's care details, since materials and trims vary.

A packable hat is made to fold or crush into a bag and recover its shape when you take it out. A shapeable brim lets you bend it up or down to block sun or change the look. Some hats offer both, so check each listing.

Most Coolibar hats come in S/M, L/XL, or XXL, and some styles are One Size. Many listings give the head circumference for each size, so measure around your head just above the ears and match that number to the size chart.

UPF comes from the fabric's tight weave and fibers, so it generally holds up with normal care. Stretching, heavy wear, or fading can reduce protection over time. Follow the care instructions and replace a hat once the fabric looks thin or worn.