Costa Mainsail Sunglasses review: Compelling proof makes me a believer

The Costa Mainsail sunglasses are designed to be a go-to pair for every outing and adventure. The stylish frames are matched with the performance of patented technology lenses. Perfect for staying relaxed on land and ready for anything while out on water.


The first time I put the Costa Mainsail sunglasses on I immediately notice how they dramatically cut the glare. The colors are enhanced, richer, and more fully saturated. I can visibly detect how the Mainsail enhances reds, greens, and blues, while filtering out harsh yellows. I see objects more clearly and with greater precision at further distances.

The frames rest comfortably on the bridge of my nose. They grip and stay in place without pinching – even with sunscreen and sweat. I love how the temple arm doesn’t rest or weigh down on my ears. Rather they have just the right pressure to gently hold in place against my head above and behind my ear. I especially like how the nose and temple grips are built into the frame. This means I don’t have to worry about rubber pieces peeling off over time. Additionally, the grips have grooves to channel sweat and water away so they stay put regardless of the conditions.

Photo Credit: Costa

My only note is the Mainsail weighs slightly more than a conventional pair of sunglasses (especially if you choose the higher clarity glass lenses). Which is more of a preference than an actual complaint. This weight differential is clearly due to the quality and durability they provide. Honestly, once I start wearing them I quickly forget about the additional weight and comfortability wear them all day.


Time to put the Costa Mainsail sunglasses to the test. I watch my lure dart through the water. The clarity with which I can see into the depths is startling. It is like someone stripped away the top layer of the water. I do multiple checks with and without the glasses. The clarity and visibility is mesmerizing – I’m almost too distracted by all that I can see to even focus in fishing.

Suddenly, he emerges from the depths like a cheetah exploding from the undergrowth after its prey. His gaping mouth lunges – just missing my lure. Time slows as his body arcs; the silvery belly flashes like the blade of a scimitar. Quickly, almost reflexively, I flick my wrists and adjust my reeling.

In response he reengages attacking my lure again. This time I watch as my lure momentarily disappears into his cavernous mouth. Instinctively, I flip my wrists the other direction to set the hook into his cheek rather than pulling it from his grasp.

Before I can say “fish on” the battle explodes to the surface. I faintly hear my startled boatmate gasp. The Large Mouth Bass water dance has begun. After several breathless minutes of man versus fish struggle, I swing him alongside the boat and land him. Once we start taking photos I realize he is even bigger than I thought. Here is the picture to prove it:

As the adrenaline begins to wear off, my boatmate asks me how I managed to catch him. I realize then that it is only because I saw him miss my lure and was able to adjust my retrieval. Otherwise, I may have never even realized that he had gone after my lure. I would have just reeled my lure right past him and launched into my next cast in another area. Which made me think… how many other fish have I missed, simply by failing to even see them!?! Rather than focus on that thought, I decide then and there that the Costa Mainsail are now a fishing mainstay.


The Costa Mainsail come with premium polarized 580 lenses. This means greater filtering of reflective glare – essential for anyone on the water or outdoors. They also provide 100% UV protection. The 580 lenses multi-patented technology manages light to enhance colors and protect your eyes. (Lens are available in higher clarity glass or lighter weight polycarbonate). The C-Wall coating delivers an extra barrier that is both scratch-resistant and repels oil, sweat, and water for simple cleaning.

The frames are stylish and loaded with features. The Mainsail are made with high-quality materials and block excess light with micro side shields and hooding. Costa has improved the frames with Hydrolite grips on the temples. Additionally, eyewire drains and channels keep sweat and water out of your eyes. So, you get the performance you need, with the style you want.


The Mainsail provides all the durability I need with the comfort I want. I love how the lenses are resilient, and scratch-resistant for worry free use. Optimal for high contrast vision and sight fishing in full sun, they won’t disappoint. The Costa Mainsail is ideal for day-to-day wear with their stylish look and exceptional performance.

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