Mares Women’s Trilastic Long Sleeve Rash Guard

Mares Women's Trilastic Rash Guard Shirt Long Sleeve – Women's Long-Sleeve Sun and Skin Protection

The Mares Women's Trilastic Rash Guard Shirt is a lightweight, long-sleeve top built to protect your skin in and around the water.

If you snorkel, dive recreationally, or spend long days on a boat or at the beach, this is the kind of layer that quietly earns its place in your bag.

What it protects you from

The most immediate job of any rash guard is keeping your skin safe, and the Trilastic does this on two fronts.

First, sun. The fabric carries a UPF 30+ rating, meaning it blocks the majority of harmful UV rays. That matters when you are floating on the surface during a snorkel, waiting on a dive boat, or doing back-to-back dives in shallow tropical water where sun exposure adds up fast.

Second, abrasion and marine contact. Long sleeves cover your forearms, which are the first thing to brush against coral, rock, or a wetsuit zipper. They also give you a thin barrier against stinging plankton and jellyfish tentacles that you might not even see in the water.

Wearing it on its own versus under a wetsuit

In warm water, the Trilastic works perfectly as a standalone top. It is thin enough to feel comfortable in tropical conditions and light enough that it dries quickly between dives or after you come out of the water.

In cooler conditions, it is designed to go underneath a wetsuit or shorty. The 85% polyester and 15% spandex blend is deliberately smooth and close-fitting, so your wetsuit slides over it without bunching or dragging. That slick surface also adds a small amount of extra warmth between you and the neoprene, which is useful when the water sits at the cooler edge of what your suit is rated for.

Fit and comfort

The seams are flat-lock stitched, which means they lie flat against your skin rather than sitting up in a ridge. This is the detail that separates a rash guard you can wear for a full day from one that leaves red lines across your arms after an hour.

The spandex content keeps the fabric stretchy in all directions, so you are not fighting the shirt when you reach overhead to grab a line or pull on fins.

Sizing runs across seven sizes from 4 to 16, which covers a reasonably wide range. Because rash guards are meant to sit close to the body, it is worth checking the specific size chart before ordering.

Who this is not for

If your water is cold enough to need a full wetsuit for thermal protection, the Trilastic alone will not keep you warm. It is less than 2mm thick and offers minimal insulation by itself. Think of it as a comfort and protection layer, not a thermal one.

It is also not a replacement for sunscreen on exposed skin. Your face, neck, and hands still need coverage.

Beyond diving

The shirt is not limited to scuba or snorkeling. Mares positions it for water sports broadly, so if you kayak, paddleboard, or spend time surfing, it works in those settings just as well. The quick-drying fabric means you are not stuck in a wet shirt the moment you step out of the water.

For any woman who spends serious time in or around the water and wants reliable sun protection and skin coverage without the bulk of a wetsuit, the Mares Women's Trilastic Rash Guard Shirt is a practical, well-constructed choice.