| Waist | Hip | Size | |
| XXS | 23-24" | 33-34" | Y14-00 |
| XS | 24-25" | 35-36" | 0-2 |
| S | 26-27" | 37-38" | 4-6 |
| M | 27-29" | 39-40" | 8-10 |
| L | 30-32" | 41-42" | 12-14 |
| XL | 33-35" | 43-44" | 16-18 |
| 1X | 37-39" | 44-46" | 16-18 |
| 2X | 41-43" | 48-50" | 20-22 |
| 3X | 45-47" | 52-54" | 24-26 |
| 4X | 49-51" | 56-58" | 28-30 |
| 5X | 53-55" | 60-62" | 32-34 |
For the perfect fit, don’t take a wild guess — take your hip
measurement! Standing with your feet together, wrap a soft
measuring tape around the widest part of your lower hip.
Check out our Model Size Guide
The fabric for our BASE undies is designed to have a
snug fit that moves with you. If you're between sizes, we
recommend trying the larger size for BASE.
Our specially engineered lining combines super-absorbent Truetex™ technology with a leak-proof lining that absorb 4 tampons worth of fluid. Use the removable booster for an additional 4 tampons of absorbency.
No detectable levels of PFAS have been found in our underwear, based on a detectable limit of one part per million.
Nope! Our undies were built to completely replace pads and tampons. They make great backup protection with tampons or menstrual cups, too.
Our undies absorb 4 tampons worth of fluid on their own, but if you need a little extra you can add the optional booster for an extra 4 tampons worth. Just tuck the ends into the slits at either end of the gusset.
Our undies were made to fit into your regular laundry routine. Just rinse the gusset in cool water before washing in the machine with your regular laundry. Hang to dry where possible - it saves energy and prolongs the life of your undies!
