

First Line Leakproof Bikini
Using Internet Explorer will cause problems with your order. Please use a supported browser like Chrome, Firefox, Microsoft Edge, or Safari to shop TomboyX.
No leaks, no mess, no worries. First Line is here to keep you dry and on the go (or on the couch). With built-in leak protection for light days and incontinence, you’ll be able to rest, move, and breathe easy. And hey — they’re antibacterial and odor-repellent, all while looking and feeling just like your favorite Tomboys.
First Line underwear is made with OEKO-TEX® 100 Certified fabrics which are free from chemicals that are toxic to humans including PFOS and PFOA chemicals that have been shown to cause infertility or cancer. Learn more.
- Looks and fits just like regular TomboyX Underwear
- 95% OEKO-TEX®-certified cotton, 5% spandex
- Holds 8 tsps of liquid
- Odor-resistant
- Smooth, durable flatlock seams won’t irritate or chafe
- Machine wash cold in a mesh bag, line dries overnight. Avoid machine drying.
Fabrics & Technology


TENCEL™ Modal
The luxurious companion to cotton. Supersoft, breathable and stretches to meet you.
Shop TENCEL™ Modal

Traveler
Quick-drying, durable and ultralight performance fabric. Anti-bacterial and anti-microbial.
Shop Traveler

First Line Leakproof
Your first line of defense — our classic cotton armed with leak protection for light period days and incontinence.
Shop First Line