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Apparel & Fit

What size base layer do I need?

A base layer should fit close to the skin to wick sweat. Pick by chest, and lean to the smaller size for a true performance fit.

Enter your chest to see your recommended size.

Base layer size chart

Your chestRecommended size
Chest under 86 cm (about 34 in)XS base layer
Chest 86 to 94 cm (about 34 to 37 in)S base layer
Chest 94 to 102 cm (about 37 to 40 in)M base layer
Chest 102 to 110 cm (about 40 to 43 in)L base layer
Chest 110 cm and up (about 43 in and up)XL base layer

How to measure

  1. Measure your chest at the fullest point.
  2. For base layers, a snug fit beats a loose one.
  3. If between sizes, choose the smaller for better wicking.

What changes your size

Compression fit wantedSize down one range.
Relaxed everyday fitChoose the larger size.
Tall torsoLook for a Tall cut to keep the hem tucked.
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FAQ

Should a base layer be tight?
Yes — a close fit wicks moisture and traps warmth better.
How do I pick base layer size?
By chest measurement, rounding down if between sizes.