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an honest pair of underwear

Polyester is plastic. Ours is seaweed and cotton.

No plastic in the fabric, the packaging, or the mailer — and every certification published, down to the thread. We'd rather show you than tell you.

GOTS OrganicOEKO-TEX® 100Cradle to Cradle GoldFSCGRS Recycled ThreadPlastic-Free Shipping
anti-greenwash, by design

Most brands hide their materials. We frame ours.

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transparency
An ingredient list you can pronounce — every certification disclosed, down to the thread.
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circularity
The fabric biodegrades within 41 days. Even our stretch fibre returns to living soil.
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ethics
Small batches, ethically sewn in Sri Lanka. We visited the factory; then we put our name on it.
the full label

70% cotton. 23% seaweed. 7% stretch. That's it.

No mystery blends, no "performance finishes." Take your time with it.

70%

GOTS Organic Cotton

Grown without pesticides. The soft foundation of every piece.

23%

Icelandic Seaweed & Eucalyptus

SeaCell™ — vitamins, antioxidants, ocean minerals.

7%

ROICA™ V550 Elastane

PFAS-free, Cradle to Cradle Gold, degrades in living soil.

0%

Everything else

No synthetic dyes, no BPA, no PFAS, no plastic packaging.

the life of the garment

What happens after you buy it

Most underwear outlives its owner — in a landfill. Here's the slower, kinder timeline we made instead.

Day 0 — you order

Made to order, in a small batch

No overstock, no warehouse mountain. Cut once, with care — small because that's how it's done right.

Day 14 — it arrives

Zero plastic at your door

No poly mailer, no plastic tags, no film. Compostable packaging, FSC paper. The unboxing is the proof.

Years 1–5 — you wear it

It softens, it lasts

88% of seaweed nutrients still present after fifty washes. It only gets better with time.

The end — it returns

41 days to compost

The fabric biodegrades and returns to the earth — while conventional synthetics linger for 200+ years.

side by side, plainly

The honest comparison

The check
A typical synthetic pair
A Kiseau pair
What it's made of
Polyester / nylon — petroleum plastic
Organic cotton + Icelandic seaweed
BPA & PFAS
Tested up to 22× safety limits
None — C2C Gold verified
Microplastic shedding
Every wash
Zero — no plastic to shed
End of life
200+ years in landfill
Composts in 41 days
Who made it
Undisclosed
Ethically sewn in Sri Lanka, named factory
Packaging
Poly mailer
No plastic. Not even the mailer.
the collection

Four cuts, made to keep.

Each in a quiet palette of earth tones, dyed gently or not at all. Buy less, buy once — we'll be here.

Kiseau bralette in charcoal — sustainable women's lingerie made from Icelandic seaweed-infused organic cotton, flat lay front view Kiseau Charcoal Cheeky Bikini and Bralette seated view — toxin-free seaweed organic cotton lingerie set

Everyday Bralette

$52 · S–L
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Kiseau high waist brief underwear in charcoal — sustainable women's underwear made from Icelandic seaweed-infused organic cotton, flat lay front view Kiseau Charcoal High Waist Brief and Bralette back view with Kiseau logo tags — toxin-free seaweed organic cotton

High Waist Brief

$29 · XS–XL
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Kiseau cheeky bikini underwear in charcoal — sustainable women's underwear made from Icelandic seaweed-infused organic cotton, flat lay front view Kiseau Charcoal Cheeky Bikini and Bralette front view — seaweed-infused organic cotton underwear and lingerie set

Cheeky Bikini

$28 · XS–XL
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Kiseau classic thong underwear in charcoal — sustainable women's underwear made from Icelandic seaweed-infused organic cotton, flat lay front view Kiseau Charcoal Classic Thong waistband detail with Bralette — seaweed organic cotton underwear

Classic Thong

$27 · XS–XL
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in your own time

Buy less. Buy once. Buy well.

Made to order, made to last, made to return to the earth when it's done. That's the whole pitch — the rest is in the label.

See the collection