First Line Leakproof 9" Boxer Briefs
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. Our trunks feature a floating gusset that can fit a pad with wings for some extra coverage when you need it. 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.
- Fit-tested on all body types, sizes XS-6X
- 95% OEKO-TEX Certified cotton, 5% spandex
- Signature stay-put silky soft TomboyX waistband
- Mid rise fit, 9" inseam
- Holds 4 tsps of liquid
- Smooth, durable flatlock seams won’t irritate or chafe
- Machine wash cold in a mesh bag, line dry overnight. Avoid machine drying.
Fabrics & Technology
Our classic soft jersey knit holds its shape after many wear and care cycles.Shop Cotton
The luxurious companion to cotton. Supersoft, breathable and stretches to meet you.Shop Micromodal
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