Sierra Whiskey Co. | Tactical Apparel & Undertac Underwear

Sierra Whiskey Co Undertac tactical underwear waistband close-up showing premium construction and Escape and Evasion pocket

BUILT FOR REAL-WORLD OPERATIONS

Precision-Engineered Tactical Underwear. Field-Tested. Mission-Ready. Proven.

Shop Undertac Underwear

OVER 1 MILLION VIEWS

Why This Underwear Went Viral

Tactical Belle tested the Escape & Evasion Pocket in the real world. See why Undertac is trusted when it matters most.

SHOP UNDERTAC

Best Sellers

Undertac Infantry Boxer Brief

$31.99

Undertac Recon Boxer Brief

$37.99

Undertac Recon Boxer Brief Opsec Camo Mens Underwear Waistband

Undertac Recon OPSEC Boxer Brief

$37.99

Undertac Sortie Boyshort Night Ops Black Womens Underwear Angle

Undertac Sortie Boyshort Night Ops Black Womens Underwear Back

Sortie Women's Boy Short

TESTIMONIALS

Built for Real-World Use. Trusted by Operators.

Real feedback from the guys who don’t get to “try again tomorrow.”

“As an operator on a Special Forces ODA I have finally found a pair of underwear that I like. They keep you from chafing while rucking over mountain tops on infills, and dry quickly after a water op. The fly design that Sierra Whiskey came up with is really top notch. Super easy to do your business even when you're wearing full kit and a 100 pound ruck. The whole ODA rocks these Undertac's and none of us will go back to wearing what we did before.”

Dan Special Forces Operator

Shop Undertac Read More Reviews

“Hands down the best underwear on the market, whether you are a member of the Armed Forces, Law Enforcement community, or every day carry citizen. These underwear are amazingly comfortable and highly innovative. They allow for easy access to do your business while still maintaining your kit and equipment. Sierra Whiskey Company really set themselves apart from their competitors.”

Dave Special Forces Operator

Shop Undertac Read More Reviews

Not Just for Operators

★★★★★
"Suitably warm, not too warm, not too cool, just right — not bulky, easy movement. You generally get what you pay for, and this is a good value proposition."
Bradley L.
UrbanOps Hoodie

★★★★★
"These are my Ranger School underwear. No spandex allowed there, so I panicked — then found these. They stay fresh longer, breathe better, and I've worn the same pair up to 5 days in the field with zero issues."
Christian K.
nfantry Boxer Brief

★★★★★
"Totally worth every penny. This fabric isn't in the same league as your usual UA or Nike briefs. Don't miss out on the opportunity to experience what real briefs should feel like."
C.R.
Recon Boxer Brief

★★★★★
"Finally a pair of briefs that stay put. My husband's a Marine veteran with muscular thighs — every brief he tried was crap, even the ones made for sweating. He was so amazed after the first pair, I ordered three
more two days later."
Corey R.
Infantry Boxer Brief

★★★★★
"This is my husband's favorite underwear he's ever worn. He especially likes the one-handed quick draw fly. We've been slowly replacing all his underwear with it — it seemed pricey at first, but it's outlasted everything else we bought at the same time."
Tarrah F.
Infantry Boxer Brief

★★★★★
"My husband religiously wears Undertac and urged me to try the women's version. Comfortable, stylish, and I didn't find the waistband uncomfortable at all — it just felt secure. My husband loves how they look on
me, and honestly, so do I."
Chaz C.
Sortie Women's Boy Short

★★★★★
"I normally get shirts from 9Line, Grunt Style, Relentless Defender — but these fit absolutely perfect, like they were tailored
for me. Clean look, soft but sturdy. Looking forward to repping SWCo to anyone who'll listen."
Jon S.
EDC Tee Shirt

EXPLORE THE LINEUP

FIELD-TESTED IN AFRICA

BY U.S. SPECIAL FORCES OPERATORS

Undertac Infantry was developed alongside a 12-man Special Forces Operational Detachment Alpha (SFOD-A) — elite Green Berets operating in one of the most unforgiving climates on earth.

From sunrise to sundown, through relentless heat and harsh terrain, Undertac endured real-world operational conditions where gear failure isn’t an inconvenience — it’s unacceptable.

If it meets their standards, it exceeds yours.

African savanna acacia tree at sunset representing Sierra Whiskey Co Undertac Infantry field testing

WHY SIERRA WHISKEY CO.

Secure Checkout

SSL-encrypted checkout

Mission Driven

Supports veteran-run anti-trafficking operations

Fast Shipping

Ships from Wisconsin, USA

RETURNS

60-Day Hassle-free returns

Forged Where Failure Wasn’t an Option

Field-tested in the harshest environments on earth.

Explore Undertac Infantry