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WunderUndies

Briefs Trial Pack - Soft Seams

Briefs Trial Pack - Soft Seams

Find My Size

$12 with coupon

A Find My Size Trial Pack includes 2 pairs of WunderUndies in consecutive sizes, in the same design and style. Please consult the size chart (below) to decide which 2 sizes you'd like to try. Use coupon 2FOR12 at checkout to get the discount. If you get one that's too small, give it to a friend!

*New Customers Only

Design
Size Group

PRODUCT DESCRIPTION

This listing is for the Find My Size WunderUndies Briefs Trial Pack!

We have found that while kids love their WunderUndies, they are very particular about their sizing. Some like them looser and some like them tighter. So the Find My Size Trial Packs were invented! With this trial pack you will receive 2 pairs of WunderUndies briefs in 2 different sizes. This way you can find the size that suits your child the best. The trial pack is for new customers only!

WunderUndies briefs are kids underwear that are sensory friendly! They’re made of super soft and environmentally friendly bamboo and organic cotton fabric. These undies are elastic-free and instead have fabric bands for the waist and leg bands. But don’t worry that doesn’t mean they’ll fall down! They will be snug on your child’s waist in the perfect way.

Once your kiddo tries them, they won’t want anything else! And neither will you.

SOFT VS FLAT SEAM BOXER SIZE

With WunderUndies first round of boxers, it quickly became clear that they ran small. So with the next round we made some needed changes. They are:
1. We shifted everything one size. Our old size 12s are now size 10s and so on and so forth.
2. We enlarged the waistbands ever so slightly. 

If you have bought from us before and are worried about what size might fit your child now, you are welcome to get another trial pack. But if you are new to WunderUndies we believe that the size chart above now more accurately reflects the best fit for our Flat Seam undies. If you are buying Soft Seam Undies, consider sizing up. 

As always, we highly recommend getting a trial pack first.

CARE INSTRUCTIONS

Some people see bamboo fabric and worry that it will be hard to care for. It's not! Many customers have praised the durability of WunderUndies. Here's what you need to know:

Machine wash cold with mild detergent. No fabric softener. Dry on low. If you feel the need to iron your undies, do that on low too. These are the practices for the longest lasting undies.

OUR BAMBOO COTTON BLEND

Our fabric blend of 67% bamboo, 28% cotton, and 5% spandex is crafted to provide unmatched comfort, durability, and versatility. Bamboo offers exceptional softness, breathability, and moisture-wicking properties, making it perfect for sensitive skin and active kids. Cotton adds strength and structure, ensuring long-lasting wear, while the addition of spandex delivers just the right amount of stretch for a snug, flexible fit. This thoughtful combination creates underwear that feels gentle, moves effortlessly, and stands up to everyday play, all while supporting sensory-friendly comfort.

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Size Chart

Size Hips (in)
2T 20
3T 20.5
4T 21.5
6 23
8 25
10 28
12 30

The waistband on WunderUndies is very snug. If your child doesn't like snug clothing, consider sizing up.