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Original Plain Black

$ 26.00
Select my color — Plain Black

Made in USA

Organic Cotton


The ultimate undies in the always faithful plain black option. 


Kanda is wearing a size 2XL Original

Coco is wearing a size 3XL Original

Jaguar is wearing a size MED Original

Krista is wearing a size XL Original

Fit models (in Vanilla):

Breana is wearing a size 2XL Original: 5'4" tall, 46” bust, 37” waist, 53” hips

Caitlin is wearing a size MED Original: 5'5" tall, 34" bust, 30" waist, 40" hips

The Original comfy undies that don't go up your bum. In sizes SM - 4XL this very comfortable full brief sits in the natural crease at the top of the leg and usually hits just below the belly button. The Original is a higher rise, but not a high waisted undie. This is our most popular style and easily fits many body types. 

Thunderpants 90% organic cotton/10% spandex fabric is sturdy, very stretchy, and has great retention to give our garments just enough stretch and bounce back. It helps the undies to stay up and on, and the other garments to keep their shape without sagging or bagging. We use the same soft organic cotton blend to cut our binding into a wide strip instead of using elastic so there is never any irritating elastic against your skin. All the garments are made locally and lovingly in Portland, OR.

To preserve the vibrant colors and life of the fabric we suggest you do not soak or bleach your Thunderpants items. Use a gentle detergent in a cold machine wash and dry your Thunderpants on the line (they will survive drying on low, but may fade a bit and cut down slightly on longevity). If you do wash warm or dry, make sure not to use too much heat as heat will break down the spandex! 

Original Plain Black

$ 26.00
Customer Reviews
4.9 Based on 483 Reviews
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Deb C.
Canada Canada

Fabulous Product

This is my 3rd purchase. So glad to find a company that makes proper underwear and in cotton. Well worth the investment.

Liv C.
United States United States

Organic & well made!

Great underwear, organic cotton, wrapped elastic band around waist & legs, very well made to boot. Love these underwear! They also stay put, they don’t slide around or roll up on you.

diane f.
United States United States

Excellent undies

Just Just like my other pair of thunderpants, these are comfortable, durable, well-made, and all-around lovely! I think they are worth the higher price point for the quality. It’s evident these will last.

diane f.
United States United States


I did a bunch of research on several different undies, then bought pairs from a handful of companies. These are the best best best best best! They are incredibly well-made, comfortable, and really cute. I have a lot of sensory issues and these cost me no problems. Highly recommend and will definitely be buying more!

Linda R.
United States United States

My go to, leave me along, undie.

Not terribly sexy, but OMG they wear like second skin and it's made HERE! They are comfortable in exercising, hanging around, and most important they are my jeans undie. Priced reasonably and I'll say it again it's USA made.