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Why We Built This

Because the sun is bright! Adventure-filled lifestyles deserve the best eyewear.

Why It's Different

Two brands, one common ethos. Plus, these frames combine outdoor functionality with superb style.

About This Product


We’ve partnered with Sunski to bring you a pair of Cotopaxi-inspired sunglasses. Meet Treeline: Designed for adventures at sea level and high altitudes alike, this unisex, medium-large frame is a must-have for mountain pursuits, water sports, and worldwide travels.

A premier performance style, the Treeline mixes a classic aviator with the iconic glacier goggle. Removable magnetic sun shields protect the eyes from side glare, while perforations prevent fogging and enhance peripheral vision. This Sunski favorite isn't just great for snow days! Extra dark lenses and sun shields make these a top pick if you spend extended amounts of time in the snow or on the water.

The Treeline is a medium-large sized frame ideal for high glare conditions. All Treeline lenses are polarized, block 100% UVA/UVB/UV400 wavelengths and pass the FDA basic impact test.


  • Polarized Lenses
  • Removable Sun Shields
  • SuperLight Recycled Frames
  • All-Day Comfortable Fit
  • Hard Case Included
  • Lifetime Warranty


  • Weight: 28.1 grams
  • Wrap & Angle: Maximum
  • Temple Width: 141 mm
  • Bridge Width: 22 mm
  • Lens Width: 50 mm

Behind The Design

Our Giving Model

Cotopaxi ties its earnings to impact by allocating 1% of annual revenues to the Cotopaxi Foundation. The foundation awards grants to outstanding nonprofit partners who are carefully selected for their track records at improving the human condition and alleviating poverty. This year alone, the foundation has awarded 34 individual grants, directly assisted 750,000 people, and donated over $400,000.

Certified B Corp

Cotopaxi is B Corp Certified. This means we have passed rigorous standards of ethical conduct. Learn more about B Corp.

Behind The Design

Designing For Sustainability

Impact starts with how we make our products. That means taking ethics into account during every phase of a product’s lifecycle—from its design to its manufacture and sale. Designing for sustainability is our priority, and we aim to create products you’ll wear for years to come. As part of the Sustainable Apparel Coalition, we have the tools to audit our suppliers to the highest standard. Beyond agreeing to our rigorous code of conduct—which protects workers and insists on fair wages—all of our suppliers are dedicated to best-in-class practices across the board.

Cotopaxi In The Wild


Cotopaxi Cotopaxi x Sunski Treeline Sunglass SUN-TL-BIS 89.00
Cotopaxi x Sunski Treeline Sunglass has a rating of 4.5 stars based on 4 reviews.