Detachable

£24.95£18.71
Detachable - Light Absorbency

Wear on heavy days

holds 2 tampons' worth

  • Wear for up to 12 hours on heavier days
  • Holds four tampons' worth or 20ml
  • For periods, leaks & incontinence 
  • Great for day and night.
  • OEKO-Tex certified materials

Buy more + save more.

Detachable 

Wear on lighter days

holds 2 tampons' worth / 10ml

£24.95£18.71

  • Wear for up to 8 hours on lighter days
  • Holds two tampons' worth or 10ml
  • For periods, leaks & incontinence 
  • Great for day and night.
  • OEKO-Tex certified materials

Buy more + save more.

Try them risk-free!

If you're not period-ing better within 60 days, we'll give you your money back.

Style + fit

Ever wanted to change your undies without getting completely undressed? 


Our simple side clasps allow you to change anywhere, without stepping foot off the ground. 


So whether you're between meetings, on a long flight, or just had a sweaty work out - we got you covered.

Fabric + care

Inner and Outer: 95% Modal 5% Elastane, Trim: 100% Polyester,  Gusset: 100% cotton, breathable PUL


Care: Quick rinse 🚿 40 degree wash 👌🏽 Hang to dry ✌🏿 No bleach or fabric softener ⚠️

Sustainably sourced

Fast + free UK shipping

Ethically manufactured

We give to girls in need

Customer Reviews

Based on 7 reviews
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(6)
14%
(1)
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D
D.B.
Flow: Heavy
Products used: FLUX Undies, obvs!
Best eco friendly underwear

I have a few from different brands but these are my favourite. When will you stock up. What to get a second pair.

E
E.
Flow: Heavy
Products used: FLUX Undies, obvs!
Impressed

There was a small amount of leaking at the seams the first few wears but after a few washes this stopped and the absorbency seemed to dramatically improve and they’re really good. Super comfy too and love the clips.

A
A.C.
Flow: Moderate
Products used: Disposable pads, Menstrual cup
High expectation… fulfilled! - Grandi aspettative… soddisfatte!

I met fluxundies.com thanks to this underpant’s type whose practicality impressed me: I was searching for an absorbency slip, useful for those times I realize my period start unexpectedly, with in intention, at the same time, to replace completely disposable pads. The lateral closing on the both sides ensures this practicality that is very useful when I am away from home. I am very satisfied with my purchase… I hope that it will restocked soon.

Ho conosciuto fluxundies.com grazie a questo tipo di slip che per la sua praticità mi aveva colpito: cercavo infatti uno slip assorbente utile per quando mi accorgo inaspettatamente di avere le mestruazioni, volendo, allo stesso tempo, sostituire completamente gli assorbenti usa e getta. La chiusura laterale da entrambi i lati assicura questa comodità che si rivela utilissima quando sono fuori casa. Sono veramente soddisfatta del mio acquisto… spero venga riassortito presto.

N
N.I.
Flow: Heavy
Products used: Menstrual cup
Very poor quality

These arrived already broken away from the clasp on one side, and hanging by a thread on the other. I never even got chance to put them on.

Very slow response from customer services. They asked me to send them back at my own expense and they would send a replacement. No apology, no offer of refund or new item. Disappointed with both quality and customer service.

I didn’t want to throw good money after bad so I’ve just left it. However I have no faith in this company or product.

  • How They Work
  • Money-Back Guarantee
  • Find Your Size
  • FAQ's

Moisture-wicking

Soft material wicks moisture and dries fast

Anti-microbial

Prevents bacteria building up and keeps smells away

Super absorbent

Absorbs liquid without feeling bulky or heavy

Leak-proof

Breathable layer prevents leaks and stains

Moisture-wicking

Soft material draws moisture away and dries fast

Anti-microbial

Prevents bacteria building up and keeps smells away

Super absorbent

Absorbs moisture and liquid without feeling heavy or bulky

Leak-proof

Breathable layer prevents leaks and stains all day

try our period-proof undies risk-free

if you're not period-ing better within 60 days, we'll give you your money back. no questions asked.

what is your return policy?

We offer free returns and exchanges within 60 days of purchase, no questions asked! Just visit our Return & Exchange Centre to get started.

how long can i wear them?

If cared for properly, our undies are likely to have a maximum tech performance of approximately 3 years. This means washing them on a 30-40 degree wash with the rest of your delicates, never using bleach or fabric softener, and hang drying! In terms of length of wear, we measure our undies by absorbency with our highest absorbency styles holding 4 tampons worth of fluid. For some customers, that means wearing them the whole day and for others that may mean carrying an extra pair of FLUX Undies as a backup. 

how do they work?

FLUX Undies are underwear that absorbs your period. Every pair is made with technology that absorbs your flow, wicks moisture, controls odour, and prevents leaks — leaving you fresh and dry. Take a look at our How it Works page to learn more.

how do i find the right size?

We recommend following the hip measurement, as most of our styles sit on the hips. Be sure to measure your hips at their widest point to find the most accurate size for you! In case you don't have a tape measure, you can use the size you usually are most comfortable with for your underwear. We recommend the undies fit snuggly, but not so tight that it's uncomfortable. For reference, you can check out our size chart.