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    Black period underwear (medium-heavy flow)

    Unit price  per 
    Black period underwear (medium-heavy flow)

    Ultra comfortable, super flattering.

    • We've got you covered: This beauty holds the same as three tampons/pads, making you feel secure and confident throughout the day (or night).
    • Gorgeous printed gusset: Say goodbye to stain-shame and be empowered to celebrate your natural & normal bodily functions. Any staining blends with the unique print to create your own design - because you, my dear, are a masterpiece!
    • Clean ingredients: Fri Period underwear is made without using PFAS or other chemical nasties. The main body is made from US-grown organic cotton and the gusset is comprised of several fabrics (also made in 🇺🇸) that work together to trap fluid and provide all-day comfort and confidence.
    • Your perfect fit: The high waist and full backside coverage will leave you feeling supported yet not constricted. 

    New to period underwear? Have some questions? We've got your back - click here.


    Customer Reviews

    Based on 9 reviews

    Product is a bit tight around the thighs needs more stretch for the big girls

    Incredible product

    These underwear exceeded all my expectations - in terms of fit, comfort and absorbency. Absolutely brilliant - I need more!

    Bianca S
    Recommend for all flows

    My period is pretty heavy and these did the job. They were comfortable and leak-free all day. Also really like wearing them at night as doesn’t “feel” like I’m wearing everything. Definitely recommend.

    Megan Houseberg
    Happy With My Recent Purchase!

    I waited to go through two cycles prior to reviewing. I wore the medium-heavy flow full brief underwear on both a medium/light day, as well as on a heavy day. They are very comfortable and held everything in with no leaking. They are easy to care for and washed well. It is great to purchase a sustainable product that is also packaged in sustainable, compostable packaging! I will definitely be purchasing again!

    Lara GILL
    Super absorbent!

    I bought a pair of these for heavy flow days and they were just what I needed - especially for night time as they are so comfortable and no need to worry about leakage! I've used re-usable pads before, but these definitely work better in terms of comfort, duration of use, and bonus they mean no unsightly bulges in your knickers and they look great! They are easy to wash too.


    All your period underwear questions answered

    Period underwear is reusable underwear specifically designed to be worn during your period (but which can be worn throughout your menstrual cycle).

    The gusset is comprised of several layers that work together to wick, absorb and hold any liquid while keeping you feeling comfortable, fresh and secure on even your heaviest period day.

    As period underwear can be washed and reused many times, it's a more sustainable, eco-friendly, and cost-effective method for managing your period compared to single-use products like tampons and pads.

    Fri Period underwear can be used by everyone, and we cater for all ages, body shapes, and sizes.

    In fact, you don't even need to get a period to wear Fri Period underwear.

    They can also be worn to assist in light bladder leakage, for postpartum wear, and anyone who would benefit from having more absorbent underwear (for example, some athletes prefer to wear period underwear during their workouts).

    Our founders also find Fri Period underwear more comfortable and dry than regular underwear during those hot and sweaty summer days!

    The gusset of Fri Period underwear is comprised of several layers, which work together to wick away, then absorb and hold your period or discharge. This means that you feel fresh and dry, while Fri Period underwear does the work of more than two regular tampons (or more for our heavier absorbency models).

    For the heavier absorbency models of Fri Period underwear, we have doubled up on the internal absorbency for an exponential level of period-containment.

    Yes! You can rest assured that Fri Period underwear are safe to wear.

    The main body of Fri Period underwear is made out of US-grown organic cotton. In our opinion, it doesn't get any better than that.

    We've had to engineer some more high-tech, high-performing fabrics for our super clever gusset, but all our fabric is sourced from the US, and made without using PFAS, lead, dioxins, heavy metals, BPA, and phthalates. No gross stuff here!

    How long you can wear your Fri Period underwear depends on your body and flow, however here are some general guidelines.

    During the day, we suggest that Fri Period underwear can be worn for up to 8-10 hours, but if you notice any saturation, leakage or discomfort, then we recommend you change sooner.

    If you have purchased the lighter absorbency model, this may be a sign that the heavier absorbency model would work better for you. If you have a very heavy flow, you may need to change your Fri Period underwear more frequently. Also, keep an eye out for our super heavy flow model, launching soon!

    Fri Period underwear can be worn overnight.

    For most of us, our flow varies throughout our period, so you may find you can wear your Fri Period underwear for longer, or shift to the lighter absorbency model for the latter part of your cycle.

    We are all different, and so exactly how we use Fri Period underwear will vary from person to person. We recommend finding a system that works best for you. Contact us if you need further help with this - we'd love to hear from you!

    The main body of Fri Period underwear is made out of US-grown organic cotton. In our opinion, it doesn't get any better than that.

    We've had to engineer some more high-tech, high-performing fabrics for our super clever gusset, but all our fabric is sourced from the US, and made without using PFAS, lead, dioxins, heavy metals, BPA, and phthalates. No gross stuff here!

    This depends on how well you care for your underwear, and how often they're used. But Fri Period underwear are made in the USA. and undergo stringent quality checks, so you can expect them to last at least several years with proper care. We haven't cut corners on making these beauties, so they are robust!

    Fri Period underwear are very easy to wash and care for - that's why we designed them! Simply wash them in your washing machine at a low temperature, and only use detergent (organic cotton doesn't like extras like softener or bleach). Lay flat or hang on the line to dry.

    Please click here for detailed instructions on how to look after your Fri Period products, plus some pro tips to get the most out of them.

    Exercise: Yes! In fact, even if you're not on your period they're a fantastic option for exercise. The fabric is breathable and moisture-wicking, helping to keep you dry and comfortable during physical activity.

    Sleep: Yes! We LOVE to wear our Fri Period underwear while we sleep, and find it is the most comfortable solution for overnight period care.

    This depends on your individual menstrual cycle and flow; what you already have in your own period care kit; and how often you're able to run a wash in your washing machine. For many people, 3-5 pairs should be enough to last a period (although would require some washing during the period). If you're unsure about taking the leap to Fri Period underwear or don't know which Fri Period underwear would best suit your flow, we recommend starting with just one pair and seeing how you get on before buying more.


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