Earn 10% Cash Back
Find Your Store
Accessibility Policy
Home Page
When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures.
Expert Help

Cart, contains 0 items

Accessibility Policy
Home Page

Cart, contains 0 items

When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures.

Up To 20% Off Full-Price Items

Shop now

EXTRA 20% Off Clearance

Shop now | Ends 11/9

Get An EXTRA $50 Cash Back*

Summit+ exclusive

Darn Tough
4 out of 5 stars
4.0 (1)

RFL Thermolite OTC Ultra-Lightweight Sock - Women's

$27.95
Color:Black

Size:

Size Chart

Quantity

Join Summit Club+ and

The RFL Thermolite OTC Ultra-Lightweight Sock disappears inside your boots

What Our Gearhead® Experts Are Saying:


"I wore the RFL Thermolite OTC Ultra-Lightweight Sock for a full day of lift laps and never felt a single seam or bunch inside my boots. My feet stayed warm without ever feeling overheated, even after hours on the mountain."


A boot that fits right starts with a sock that disappears, and the RFL Thermolite OTC Ultra-Lightweight Sock from Darn Tough is built to do exactly that. Picture buckling into your boots at the base of the lift, feet settling in smooth and snug, nothing bunching or shifting as you carve into your first run of the day.


The synthetic Thermolite fibers keep things light and insulating without adding bulk, while the True Seamless Toe technology closes off any pressure points before they start. A reinforced Achilles panel cuts down on heel lift, so the fit stays locked in from the first chairlift to the last run, run after run.


Details

  • Ultra-lightweight over-the-calf sock for skiing and snowboarding
  • Thermolite fibers insulate without adding bulk
  • True Seamless Toe eliminates pressure points
  • Reinforced Achilles reduces heel lift
  • Performance fit prevents slipping and bunching
  • Item #DRNC04C
Material
53% nylon, 42% Thermolite polyester, 5% lycra spandex
Height
over-the-calf
Weight
ultralight
Cushion
none
Manufacturer Warranty
limited lifetime
Activity
ski, snowboard

Related Categories

  1. Women's Ski Socks
  2. Women's Snowboard Socks
  3. Women's Ski Clothing
  4. Women's Snowboard Clothing
  5. Women's Ski Pants and Bibs
  6. Women's Snowboard Pants and Bibs
  7. Women's Ski Gloves and Mittens
  8. Women's Snowboard Gloves and Mittens
  9. Alpine Ski Boots
  10. Snowboard Boots

Frequently Asked Questions

  • How does the Darn Tough RFL Thermolite OTC Ultra-Lightweight Sock fit inside ski and snowboard boots?
    Its no-cushion, ultra-lightweight profile keeps bulk low for a close boot fit. The over-the-calf construction measures about 16.25 inches from heel to cuff.
  • Which size should I choose in the Darn Tough RFL Thermolite OTC sock?
    Choose by women’s US shoe size: S fits 4.5–7, M fits 7.5–9.5, and L fits 10–11.5. A close performance fit helps limit bunching inside ski boots, so don’t size up for extra warmth.
  • How does Thermolite construction balance warmth and bulk in this ski sock?
    The Darn Tough RFL uses Thermolite polyester hollow fibers designed to trap heat while keeping the sock lightweight. Its thin, no-cushion construction suits snug boots where added padding can affect fit.
  • How does the RFL Thermolite OTC manage moisture during ski days?
    The synthetic knit is moisture-wicking and quick-drying, helping manage sweat during skiing and snowboarding. It is not waterproof, so boot and shell protection handle external moisture.
  • What materials are used in the Darn Tough RFL Thermolite OTC Ultra-Lightweight Sock?
    The listed composition is 54% nylon, 43% Thermolite® polyester, and 3% Lycra. For care, machine-wash cold on a gentle cycle with the sock inside out, then tumble-dry low or hang dry.