KNOW YOUR FLOW
Absorbency Guide
Our Invisi Seamless Period Underwear - Bikini has a Moderate absorbency.
Check out the below guide to see how this level stacks up against our other products.
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Invisi Seamless Period Underwear - Bikini
Seamless protection. In Cotton.
The Invisi Seamless Period Underwear Bikini is built for everyday wear under anything — bonded flat seams sit flush against skin with no digging, virtually no visible lines, and no bulk. Designed for moderate flow, it holds up to 20–25ml so you can get through your day without thinking about it.
Why you'll love it:
- Bonded seamless construction — minimal visible panty line under fitted clothing
- Holds 20–25ml — moderate flow protection
- Lightweight and barely-there feel for all-day comfort
- Perfect under gym tights, activewear, and everyday outfits
- PFAS-free and chemical-free throughout
- Reusable and machine washable
Fabric: Cotton/ elastane outer fabric outer · Polyester inner gusset
Seamless bonded seams | Holds 20–25ml | Recycled nylon | PFAS-free | Everyday wear
●●○○○ | Moderate - Check out our absorbency guide here
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Outer fabric: 95% organic cotton, 5% elastane. Inner fabric: Polyester/ Nylon/ Breathable TPU
Step 1 Wash your Eco Period underwear before wearing / using them. This activates the EcoTech and primes it for use.
Step 2, After wearing, rinse in cold water until the blood/ fluids are mostly removed. You can do this in the shower to save water, but just do it before the water heats up past 30 degrees, as heat will set stains into the fabrics.
Step 3. Pop your undies into a delicates wash bag and into the washing machine on a cold wash. Use a liquid natural detergent.
No fabric softeners.
Step 4. Hang dry on the line outside. Line drying is best as it is kinder to the fabrics. Just don't leave them out on the line for days.
Eco Period underwear should NEVER:
Be cleansed with harsh detergents (these abrade and break down clothes which shortens their effectiveness and lifespan)
Be cleansed with fabric softeners (it's like fabric cholesterol and blocks the pathways in the fabric through which the liquid travels)
Be bleached (bleach kills everything, need we say more)
Be dry cleaned (putting the products into such a harsh environment with or without the added chemicals is bad)
Be washed in very hot water (heat breaks down the fibres and natural compounds that make these products so effective.
When your undies arrive, try them on over your regular, clean underwear before use to check the fit. Make sure to give them a wash before your first wear to improve the absorption performance.
Then to use the undies, simply wear them like you would with any of your other underwear.
How long you wear your underwear for will come down to personal preference and your flow. We recommend changing every 6-12 hours.
You might like to add
$9.90
IS IT YOUR FIRST TIME TRYING REUSABLE PERIOD CARE?
Once you start, you'll never go back to traditional single-use period care products again!
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Eco Period Australia underwear absorb your period.
Every pair is made with our signature technology that's odor-controlling, super-absorbent, and leak-resistant. This 4 layer technology works together to do it’s thing (aka keep you fresh and dry). Take a look at our How It Works page to learn more.
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Yes, our period underwear has been designed to be worn alone, with no tampons or pads required. If you wish to wear a menstrual eco cup as well, this can extend the wear time of your eco briefs.
Also the length of time you can wear each pair depends on your flow.
As a general rule, we recommend choosing heavy or super absorbency for your heavy flow days and moderate or light for your lighter days.
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This comes down to personal preference and your flow, however you can wear a pair of undies for as long as 24 hours. We find most of our customers like to change every 8-16 hours. There's no right or wrong here!
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Our range of period underwear range from Super > Light. Scroll down to check out our Absorbency Guide here to decide which level is right for you.
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Firstly, work out how many days of your cycle are heavy and moderate/light. Then, you can calculate the number of briefs you will need using this guide:
Heavy flow days:
- Within a 24 hour period, we'd recommend changing 2-3 times.
- Suggested change times - morning, midday (optional if your flow is heavy) and at the end of the day.
Moderate/light flow days:
- Within a 24 hour period, we'd recommend changing 1-2 times.
- Suggested change times - morning and at the end of the day.
So you can allow ample time for washing + drying, we suggest buying double the amount you calculate above, so you're never caught out without a clean pair to wear!
Check out our Know Your Flow page for more guidance.
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If you use period cups or pads you might not need as many pairs of period underwear.
Browse our collection of eco-pads and menstrual cups to grow your eco-friendly period solutions.
If you're often on the move and wish to change your underwear, we recommend getting a wetbag for your used underwear to store them before you're able to wash them.
We recommended washing your undies in a wash bag to protect garments in the washing machine and prolong their lifespan.
SUPER
●●●●● 30-60ml
The lining is thicker and extends to the back waist seam, so it covers you for overnights.
HEAVY
●●●●○ 25-40ml
Choose Heavy absorbency if you have a heavy flow or for your heavy flow days or for moderate incontinence. The lining extends to the back waist seams, so it covers you for overnights or when laying down on your side and back.
MODERATE/HEAVY
●●●○○ 20-30ml
Perfect to use if your flow is moderate, so think 3rd or 4th day of your period. Also for light to moderate incontinence leaks. These undies will also cover you at night as the leakproof lining extends up to the back waist seam (a thinner layer than the heavy absorbency).
MODERATE
●●○○○ 15-20ml
Choose Moderate absorbency for day-time wear, active wear and for when you just don't need that extra panel of protection up the back. Suitable for flows from 15-25 ml. The lining is generally a little thinner too, so does not feel bulky.
LIGHT
●○○○○ 10-15ml
If your flow is light, or you are using as a backup, choose light absorbency. This will provide a leakproof function and some absorbency as a backup.
Think your individual decisions won't make a difference? Think again.
The average women uses 11,000 pads, tampons and pantyliners in their lifetime.
That's a lot of landfill! It's time to make the switch to Eco Period Australia - you won't look back.
WHO WE ARE
Eco Period offers beautifully crafted, quality period garments that are made to last, and are just as good for your body as they are for the environment.
We are passionate about making a difference through our products and hope to help you transition (or continue) your journey towards zero waste, eco and organic period solutions.