REI Co-op  Active Thong Underwear - Women's

When running shorts don’t come with a built-in brief or extra layer of protection (or even when they do but the layer isn’t particularly comfortable against the skin), I will wear underwear. This product does the trick. The material is soft and smooth with no irritating edges. I didn’t notice it while running, even on long runs of over an hour. The only complaint I have is that there is a tag, and I did cut that off as I don’t like tags on my underwear (sometimes they can irritate). But other than that, it’s perfect for working out. It does seem to run a tad big, though this wasn’t a problem for me. But in the future, I will order the next size down.

I bought 3 pairs of these and they seemed great at first. But, after wearing only 3-4 times, one pair just literally starting falling apart. This is really disappointing for $15 underwear, that are supposedly for being "active." So, I'm down to 2 pair, but I hesitate to wear them. I would not buy them again.

Let me start by saying these thongs are the COMFIEST underwear I have EVER put on my body. I don’t even know that they are there. However the seems started falling apart after about 15 washes and I always air dry them. I bought them regardless of the reviews bc I thought maybe it’s a bad batch but I was wrong. The only color that seems to not unravel is the black color. If I was rich I would keep buy these and just throw them out when they got bad bc these are the only underwear I will wear. But sadly I’m a nursing student with lots of loans so I will wear my unraveling underwear until they can’t be worn no more!!

These undies are very nice. I like the thong option in active underwear which isn’t as easy to find with other brands. This is a staple that will get packed on most adventures. The material is light, stretchy, and comfortable. The rise is a little higher than I am used to, but they fit nicely under clothes, and are very comfortable for both active adventures and everyday excursions. I’ve worn mine shopping and mountain biking so far. You don’t even know you have them on. For a synthetic they are surprisingly not stinky too. Love the coral color!

I've had a hard time finding activewear/ moisture-wicking thong underwear. After purchasing one pair to try them out, I've gone on to purchase several more. These are great if you wear compression/ form fitting activewear bottoms (leggings or tights) because they don't show any lines or show through in the back if you squat or bend over. They hold up well in the wash and don't retain any odor. I hope that REI will keep these as part of their product line

Let's be honest... If you're going to buy a pair of athletic underwear, you really don't want to have to wonder what you're buying and definitely don't want to consider if it would be something you would return. So let me fill in the blanks: 1. Are they comfortable? Yes! They are very light weight and breathable. However, I would not say they would be great for activities that have a risk of chaffing (such as long runs or climbing, etc.). 2. Are they actually microbial? I spent a couple days camping and they felt okay- but it's more a preference of how clean people prefer to be, but it definitely gave me more ease of mind! 3. How do they compare to other multi-sport athletic underwear? Honestly, these are a great price point for what you will pay double for! If you prefer something a little more seamless, definitely make sure the stitching is okay by you before purchasing... But, I think these will suit most athletes! 4. How do they run size wise? Very true to size. I followed the sizing chart and they fit perfectly! 5. Is the thong uncomfortable? If you prefer this style of underwear, no. They felt like a regular thong, if not better than average! 6. Do they show underwear lines? The seams make the outline a little more prominent, but for your average pairing with other activewear, you likely won't see them! 7. What kind of activities do you suggest these for? Short runs, light climbing, mild to moderate hiking, camping and other moderate activities... Again, activities that are unlikely to cause chaffing.

I purchased several pair of these and wash and hang them to dry. They are very comfortable but I’m disappointed in the quality of the material. It has started to fray for no reason as I hand wash and hang them to dry.

This underwear is very comfortable. But its falling apart after 2, 3 wash, strings are hanging out. Please do quality control. Any cheap underwear will last longer than this.

Bought 2 pairs of these in the REI store and within an hour of wearing one of them the seam came undone and the sides did he underwear separated at the seam. Heed the warning and do not buy these. Reached out to customer service for a refund for both pairs.

I ended up having to buy some new underwear really quickly before a climbing class for Reasons, and I decided to see if I could find anything that wouldn’t show underneath my climbing pants. I loathe underwear lines. These fit super well and didn’t cut in, which is saying something with the amount of glory I’ve got going on in my curvy areas. They’re light and breathe well. I climbed a couple pitches in them, and have no complaints. Get some!