Flux Undies BoyShort Period Pants
Flux Undies BoyShort Period Pants
Flux Undies BoyShort Period Pants

Flux Undies BoyShort Period Pants

(3 Reviews)
XXS 4-6
XS 8
S 10
M 12
L 14
XL 16-18
XXL 20-22
3XL 24-26
4XL 28-30
Flux Undies
Product Detail


  • Suitable Day & Night


  • Wear for up to 12 hours on heavier days
  • Holds four tampons' worth or 20ml


  • Wear for up to 6 hours on lighter days
  • Holds two tampons' worth or 20ml

Flux Undies Boy Short Period Pants Overview

Flux Undies Boy Short Period Pants are great for periods, leaks and incontinence. When I first read the name "boy short" I expected something like tight shorts however this IS NOT what they are like at all. Flux Undies Boy Briefs are really a "midi" style pant or how I described them as your "comfy knickers." They cover your bum, have fairly deep sides but with the modern Flux waist band they look fasionable and not big granny pants!

Flux Undies have the most delicously soft tencel modal fabric. There is nothing rough or crunchy about these. Modal fabric is often found in ladies tshirt style tops to help you visualise the type of fabric is it.  The fabric is designed for comfort and to be gentle on the skin.  Tencel originates from renewable raw materials that are certified compostable and biodegradable.

Flx Undies BoyShort offer the main absorbency in the gusset of the knickers. This is great if you don't want absorbency right up to the top as some other brands do.  Concentrating the absorbency just in the gusset makes thue light absorbency option feel like normal knickers.  Anyone in my home could do the washing and not know these were anything other than a normal pair of Mummy's black pants!   The heavy days optoin the gusset area does feel more "structured" and thicker. There is more of an outline marking the changing in thickness of the fabric from the gusset to the main body of the pants.  In both absorbency options the rest of the pant is made with a double layer of modal fabric in the main body of the pant making them feel like a good quality pair of pants and no extra "padding" to feel in these areas.

The gusset gives a breathable leak proof layer and prevents any leaks. The built in moisture wicking top and absorbent layers keep you feeling fresh and dry up for up to 6 hours.



  • No Synthetic Fragrances,
  • Paraban Free
  • Vegan
  • Naturally Anti-Bacterial
  • Eco-Friendly
  • Sustainably Sourced
  • Cruelty Free
  • Reusable & Washable

They can be worn day and night and are made from OEKO-Tex certified material.


Inner: 95% Modal 5% Elastane,

Waistband: 100% Polyester, 

Gusset: Absorbent blend, Breathable PUL


  • Quick rinse 
  • 40 degree wash 
  • Hang to dry
  • No bleach or fabric softener


Pants FAQ's

How many pairs of period pants do I need?

We tend to find that 5-7 pairs of underwear are enough for the average cycle.  2 Night time pairs and 3-5 day time pairs means that you have enough to wash every other day and ensure that they dry in time for their next use.

Machine Washing Period Underwear.

Washing period pants in the washing machine is the most effective way to care for your undies.

Here is a basic guide to wash period pants:

  1. When you remove your used underwear rinse them thoroughly with cold water till the water runs clear. You can gently rub them to help remove as much blood as possible.
  2. Either pop them in your normal washing with other clothes or store them in a wet bag until wash day.
  3. Wash on a cold wash at either 30 or 40deg. You can use your normal detergent but avoid fabric softener.

Most companies will advise you to avoid harsh chemicals, fabric conditioner and tumble drying, as eventually it will lead to a shorter life span and issues with performance.

Customer Reviews (3)
Write a Review and share your opinions!
3 Reviews:

Great product and service
19 September 2021  | 

I’ve bought other brands of these ‘shorts’ before which have lasted 1 wash- these are so much better and a lot more comfy! Service was great also- very quick reply to my query. Would definitely recommend this product and company

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Great period pants
04 September 2021  | 

I really like these pants. They’re comfortable and are good for a medium-heavy flow. The first time I used them overnight they leaked a little from the side, I think I much have been sleeping on my side and it was during the heaviest part of my period. They were on all night though so I was still impressed.

The reason I haven’t given them 5 stars is because they do leak a lot of colour even after quite a few washes so make sure you wash them with black only things!

I’m a size 10-12 clothes size, and the size 12 pants fit me perfectly.

1 of 1 people found this review helpful.
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Leaks, colour bleeds and takes forever to dry
02 September 2021  | 

I've given it a try on different days in different cycles and it leaked right through the middle every single time as if it had no outer protective layer at all. Washed it on a gentle cycle adhering to the instructions and the colour bled a lot - the white letters on the waistband are now grey. I never had colour bleed issues with other brands. It also takes about three times longer to dry compared to products from other brands I've tried. I'm not sure if I received a faulty pair but I am very disappointed.

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