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Thinx

Ultra Soft Brief

Original Price

$36

Thinx underwear is not made or treated with PFAS

45-day trial
+ free returns

Don’t love 'em?
Get your $ back
no Qs asked

Thinx underwear is not made or treated with PFAS

holds up to
worth.
colorBlack
Select a color

size

size chart

buy 3, save 10%

Buy 3-4 pairs for 10% off

Buy 5-6 pairs for 15% off

Buy 7+ pairs for 20% off

Savings are applied automatically during checkout. Our custom Set discount applies to Thinx period underwear and Thinx for All Leaks bladder leak underwear (but excludes Saver Sets).

buy 3, save 10%

Buy 3-4 pairs for 10% off

Buy 5-6 pairs for 15% off

Buy 7+ pairs for 20% off

Savings are applied automatically during checkout. Our custom Set discount applies to Thinx period underwear and Thinx for All Leaks bladder leak underwear (but excludes Saver Sets).

style

A super comfy, full-coverage style made from premium Modal Cotton, featuring leakproof protection up to 12 hours. Fits true to size. 

Formerly named Modal Cotton Brief.

fit

  • Made with our LeakSafe™ barrier: Leakproof all day up to 12 hours

  • Moisture-wicking fabric helps keep you feeling dry 

  • Odor control technology helps minimize odors 

  • Thin and discreet — looks and feels like regular underwear

Thinx_Signature_All-Day-Modal-Brief_Black_Style+Fit.jpg
Our Protection Promise: Thinx underwear is designed without PFAS or any harsh substance on our Clean Commitment List.

fabric

  • body: 53% Cotton, 35% TENCEL™ Modal, 12% Elastane
  • side panels: 91% Polyamide, 9% Elastane
  • gusset 1 (wicking): 100% polyester
  • gusset 2 (absorbent): 100% polyester
  • gusset 3 (barrier): 100% polyester (polyurethane, Lava XL-N®, Suntex TN-5000)
  • Thinx underwear is not made or treated with PFAS.
  • Our underwear is certified OEKO-TEX® STANDARD 100, #20.HUS.04850 by HOHENSTEIN HTTI, 3rd party tested for the presence of harmful substances to ensure product safety.

care instructions

Wash before wear, machine wash cold with like colors, line dry. Do not iron, bleach, dry clean, or tumble dry.

Thinx Modal Cotton illustration

Ultra Soft

Our buttery-soft, premium TENCEL™ Modal Cotton blend is perfect for feeling *extra* cozy on your period.

how our period underwear works

Thinx - PDP - take the Know Your Flow quiz

find your perfect pair

Take our short quiz to get matched with undies that suit your style and needs.

Thinx - PDP - create a set

buy more, save more

Mix and match any Thinx undies — and you can save up to 20%.

FAQs