Designed in Japan
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"Very comfortable for exercise and daily use. I will be purchasing more!"
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$40.00
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$40.00
This item's price has been updated recently to ensure you get the best value.
Last priced at -
A stretchy, ultra-comfortable thong for minimalist comfort, the Siren Thong features our corespun merino wool blend fabric for durable, super-soft performance during active or casual use.
Good for:

83% Merino Wool/ 12% Nylon/ 5% Elastane, Exclusive of decoration
Machine wash cold gentle cycle. Wash with like colors. Do not use softeners. Do not bleach. Do not tumble dry. Line dry in shade. Cool iron. Do not iron print. Do not iron decoration. Do not dry clean.
Model measurements
Height: 179cm / 5'10". Waist: 62cm / 24". Anya is wearing size S.
Fit
Slim
Overall rating: 4.7492065 / 5 from 315 reviews.
The Women's Merino 150 Siren Thong is praised for its true size, great fit, and high-quality fabric. Customers appreciate its comfortable and ergonomic design, making it suitable for all-day wear. However, some customers find the gusset too small and have mixed opinions about the liners.
Review topics: ["fit","size","weather","problem","quality","fabric","material","coverage","looks","wear","design","pants","feel","comfort","band","colour","medium","texture","style","packs","waist","moisture","speed","underwear","thong","buy","pair","tags","wool","liners"].
"Very comfortable for exercise and daily use. I will be purchasing more!"
— Becca (5/5)
"These are perfect. I use these for running and skiing, the cut is excellent and the merino obviously helps with all day sports comfort."
— Angela (5/5)
"Love these! I always wait for a sale because they're pricey but this is my fourth pair over the last 2-3 years and they're all still going strong."
— Lauren M. (5/5)
"The rise of the underwear is low. Think early two thousands jeans. Otherwise pretty comfortable if you don’t try to give yourself a wedgie."
— Starlight K. (3/5)
"Great thong that doesn't dig in"
— Olga G. (5/5)
"I've tried a different brand of merino underwear and this one was much more comfortable. Thin, breathable, with a higher percentage of merino. I'm usually an XS but purchased a small based on reviews. It fits well, but I'm wondering if I could have tried an XS. Either way, I love it! Would love to see boy shorts in the beige colour also. I agree that the gusset could be longer."
— AK (4/5)
"I brought a couple pairs of these into the backcountry for nearly two weeks, they were insanely comfortable during strenuous hiking and a quick rinse refreshed them so I could wear again, and they continued to smell and feel fresh the whole trip!"
— Jen (5/5)
"I'm a yoga teacher and I move a lot. This thong makes me forget I'm wearing underwear. Ha! That's a good thing. I love that it's merino. The band is good, it lays flat, and doesn't pinch. There is no scratchy tag! Thank you!! The thong is not itchy and it doesn't slip, slide, or bunch. It washes easily in the sink or washer on cold and dries within a day on a dryer rack. Next to going commando, these are the next best thing. Expensive? Yes. And they are truly worth it. Icebreaker is the best. But I've already bought 3. One more and I'll be able to rotate throughout the week with no problem."
— Commando J. (5/5)
"I originally purchased 3 black for rowing, and came back years later to buy more in nude to wear with white linen pants and other more transparent bottoms. Very happy with the cut and quality of the old pairs and hope the new are the same. For reference I am 5'-5"", 130-135 lbs, 40"" hips and 30"" waist, athletic/curvy build."
— Chris (5/5)
"Despite the price tag on such a small bit of material, these are so comfy that I will continue to buy these! Will last a long time if hung to dry and washed on gentle and even longer if you hand wash"
— LaVa (5/5)
Find the size that fits you best based on people just like you.

Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit. If your measurements for chest and waist correspond to two different sizes, order the size indicated by your chest measurement for tops and your hip measurement for pants.
Sizing charts:
| XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|
| Waist | 24-26 | 26-28 | 28-30.5 | 30.5-33 | 33-36 | 36-40 |
| Hip | 33.5-35.5 | 35.5-38 | 38-40 | 40-42.5 | 42.5-45 | 45-48.5 |
| XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|
| Waist | 61-66 | 66-71 | 71-77 | 77-84 | 84-91 | 91-101 |
| Hip | 84-90 | 90-96 | 96-102 | 102-108 | 108-114 | 114-123 |
*Looking for the inseam length? Please refer to the product page to find out.
Our three different fits - slim, regular, and relaxed - ensure that when worn together, layers move and breathe like a single garment.



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