Icebreaker Siren Thong Review
Compare prices at 3 resellers Pros: Most comfortable fabric, well-constructed design, quick drying, true to size
Cons: Expensive, heaviest thong tested
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Icebreaker Siren Thong
|Price||$16.50 at Backcountry|
Compare at 3 sellers
|$28 List||$19.25 at Backcountry|
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|$11.25 at Backcountry|
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$14.95 at REI
|Pros||Most comfortable fabric, well-constructed design, quick drying, true to size||Silky fabric, stays in place, cute design, breathability, bonded seams prevent chafing and panty lines, quick drying||Lightweight, quick-drying, merino wool||Inexpensive, soft, quick-drying, no bulky seams||Affordable, breathable, nice waistband|
|Cons||Expensive, heaviest thong tested||Expensive, runs large||Less practical fit, expensive||Imperfect fit for some||Not very durable, flatlock seams unraveling with minimal wear|
|Bottom Line||This exceptional thong-cut garment is a super comfortable, well-designed product that excels in urban and backcountry travel||Super comfortable, breathable, and a flattering fit that allows you to forget about your undies and focus on your adventure||This is a high quality, flattering, and super comfortable bikini-cut model made out of quick drying and soft merino wool||Soft, stretchy, and quick to dry, this value-forward garment won us over without making us pay a high price||The affordable price tag is alluring, though our testers were disappointed by the fit, durability, and longer drying time|
|Rating Categories||Icebreaker Siren Thong||ExOfficio Modern Bi...||Icebreaker Siren Bi...||Under Armour Pure S...||REI Co-op Active Thong|
|Drying Time (25%)|
|Specs||Icebreaker Siren Thong||ExOfficio Modern Bi...||Icebreaker Siren Bi...||Under Armour Pure S...||REI Co-op Active Thong|
|Material||83% Merino Wool, 12% Nylon, 5% Lycra Spandex||82% Nylon, 18% Spandex||83% Merino Wool, 12% Nylon, 5% Lycra||68% Nylon, 32% Elastane||86% Polyester, 14% Spandex Mesh, 100% Cotton Liner|
|Measured Weight (oz)||.9 oz (M)||.8 oz (S)||1.1 oz (S)||0.7 oz (S)||0.4 oz (M)|
|Cuts Available||Thong, bikini, hipster||Bikini||Bikini, thong||Hipster, cheeky, thong||Bikini, thong|
Our Analysis and Test Results
The Icebreaker Merino Siren Thong stands out from the competition. The soft and comfortable merino corespun fabric feels great on the body with enough stretch to allow for freedom of movement, along with a great waistband to hold things in place. This thong received high scores in almost every testing category and became one of our go-to's as an ultralight thong for extended travel.
We believe comfort is key to any garment that you'll be traveling with for an extended period, so we began by testing each pair of underwear side by side to evaluate the level of comfort next to skin, whether or not the fabric was breathable during activity, how thick the material was when compared to other garments, and finally, the type of material the garment is constructed from.
The Merino Siren Thong earns high marks in this category because of the incredibly soft next-to-skin feel and breathability of the corespun, mostly merino fabric. The unique fabric, made out of 83% merino, 12% nylon, and 5% elastane, helps to regulate your body temperature during high activity and wick away moisture. The Siren Thong quickly became our go-to thong, even while recreating and being active. It is so comfortable that it remains unnoticeable throughout the day, which is what we want in underwear.
To score the fit for each pair of underwear, we considered the details of the cut, how well it covered our body, whether or not the material was stretchy enough to move with us, and if the waistband did its job of holding the garment in place.
The cut is true to size, offering great coverage where you want it and less where you don't, making it a great option to hide those distracting panty lines or appreciate during your next adventure. We love the waistband on this thong over the flatlock seams of other merino wool options. The stretch allows for freedom but is also tight enough to provide control so we never need to adjust. When considering overall fit, including just the right amount of stretch, the Merino Siren Thong is our favorite out of the thong cuts we put to the test.
We tested the drying time of each pair of underwear on a spring day in Victor, Idaho in between travels by soaking each pair in water, wringing them out by hand, and then hanging each pair on a line to dry in partial sun with a light breeze.
The Icebreaker Merino Siren Thong gives a top-notch performance in this category, completely dry in a time of 44 minutes. The super-soft merino fabric also dried quickly from sweat during high-performance activity, again allowing us to move freely and not become distracted by the discomfort of our underwear. We even took a dip in an alpine lake with these undies and after wringing them out, they dried on the body during movement before we even finished the descent.
We understand that every ounce counts when it comes to extended travel and carrying all your essentials on your back. To test for the overall packability, we decided to weigh each garment on our scale and then we performed a side-by-side comparison between each garment to assess which model required the least amount of space within luggage or a backpack.
Weighing in at .88 ounces, the Merino Siren Thong is heavy compared to the thong cuts we tested. We attribute this extra weight to the double merino corespun fabric which not only increases comfort, but also helps to wick moisture away from the body. We understand that selecting a thong cut over a hipkini can help to shave ounces off the weight of your pack, however, when we compared each pair for their compact size and minimal space requirements, we noticed little difference in terms of bulk. While the Siren Thong is not the lightest in the bunch, we are pleased to sacrifice a small amount of weight for luxurious comfort, fit, and breathability.
The Merino Siren Thong is one of the more expensive garments that we tested from minimal thongs to full coverage hipkinis. However, who doesn't want a little luxury when traveling away from the comfort of home? In return for your investment, you receive a high-quality, well-designed product that will make you forget you are even wearing underwear, making the Icebreaker Merino Siren Thong not only worth its weight but also worth the price.
If thongs are your preference, we strongly recommend the Icebreaker Merino Siren Thong for travel. Featuring a double merino corespun fabric that is not only quick-drying and breathable but will also keep you comfortable during your next adventure. Hands down, it's our favorite of all thong cuts we tested.
— Trish Matheny
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