How does far-infrared thermal technology work in clothing?

Far-infrared (FIR) technology uses special fibers that absorb your body's natural heat and reflect it back as far-infrared radiation. This creates a microclimate of warmth around your body, boosting perceived temperature by approximately 5°C (9°F) without adding bulk. It's the same principle used in therapeutic heating pads and NASA space suits.

Can I remove the built-in bra?

Yes. The built-in bra features removable padding with an invisible bust line. You can wear it with the bra for full support as a standalone piece, or remove the pads to use it purely as a base layer under other clothing.

What is Hush Fiber fabric?

Hush Fiber is a premium Japanese textile made from ultra-fine 1.0T fibers (1/10 the thickness of human hair). It delivers a silk-like feel against the skin while providing exceptional warmth retention. The fabric blend is 56% Nylon, 38.5% Viscose, and 5.5% Spandex.

Will this create static cling?

No. The Hush Fiber fabric is specifically treated with anti-static properties, eliminating the crackling and clinging that plagues traditional thermal underwear in dry winter conditions.

How thin is this base layer?

Extremely thin — the 1.0T fiber is 1/10 the thickness of a human hair. This means the thermal tank top adds virtually no bulk under your clothes, maintaining a streamlined silhouette while delivering +5°C warmth.

What sizes are available?

Available in S, M, L, XL, and 2XL. The stretchy Spandex blend provides a comfortable, flexible fit. We recommend checking our size chart — sizing may run slightly smaller than standard North American sizing.

CatWarm U-Neck Thermal Tank Top with Built-in Removable Bra | Infrared

Q: Does infrared-reflective fabric actually keep you warm?

Yes. An infrared-reflective knit reflects the far-infrared heat your body gives off back toward your skin, so a thin, breathable layer retains warmth without bulk. It conserves the heat you produce rather than generating heat.

Q: What is a removable bra pad and how is it different from a shelf bra?

A shelf bra is only an inner elastic band with minimal support. This tank has removable molded pads that give real shaping and coverage, and can be taken out to wash. One piece replaces a tank plus a bra.

Q: Can I wear this thermal tank as a top on its own?

Yes. The U-neckline, built-in bra and full side coverage are designed to look finished worn solo, and it also layers invisibly under sweaters.

Q: Is a thermal tank a good base layer for winter?

Yes. The infrared-reflective knit adds warmth without bulk under outer layers and stays smooth, making it an ideal lightweight winter base layer.

$50.00

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Bra Included: Built-in bra for support, but you can take it out too.
Super Soft: Made with comfy Japanese fabric you'll love to wear.
Stays Warm: Keeps you 5 degrees warmer, even on the coldest days.
Perfect Layer: Wear it under clothes for extra warmth, or on its own.

Material

Main fabric: Nylon 56%, Viscose 38.5%, Spandex 5.5%
Lining: Nylon 38%, Viscose 54%, Spandex 8%

Color: Black

Black

Black
White
Brown
Red

Size: S

S

S
M
L

Quantity

Stay warm and stylish with the CatWarm U-Neck Thermal Tank Top with Built-in Removable Bra. This tank combines super-stretch fabric with infrared-reflective technology to deliver exceptional warmth without the bulk. The built-in removable bra pads give gentle support and shaping, while the flattering U-neckline and full side coverage make it easy to wear on its own or layer under your favorite outerwear — your go-to piece for all-season comfort.

Warmth Without the Bulk — Infrared-Reflective Thermal Tank

The CatWarm U-Neck Thermal Tank is built from an infrared-reflective knit that reflects your own body heat back toward you, so you stay warm without a thick, bulky layer. The rounded U-neckline and built-in removable bra pads mean it works two ways: wear it solo as a top, or slip it under a sweater as a smooth winter base layer.

Why "Built-in Removable Bra" Beats a Shelf Bra

Most thermal tanks use a "shelf bra" — just an inner band of elastic with no real shaping. Ours uses removable molded pads: genuine support and coverage when you want it, and you can take them out to wash or to soften the look. One piece replaces a tank plus a bra.

All-Season, All-Day

Infrared-reflective knit — retains warmth, stays lightweight and breathable
Built-in removable bra pads — support with a clean, seamless line under clothes
Super-stretch & shape retention — moves with you, holds its shape wear after wear
U-neck + full side coverage — flattering solo, invisible as a base layer
4 colors, S–L — Black, White, Brown, Red

Infrared-reflective U-neck thermal tank top with built-in removable bra — front detail

U-neck thermal tank top with removable bra pads — detail

Infrared thermal tank top for women — super-stretch fabric detail

U-neck thermal tank base layer — removable molded bra pad detail

CatWarm thermal tank top with removable bra — color options Black White Brown Red

Infrared thermal tank top worn as a winter base layer

U-neck thermal tank top worn solo as a top

Warm thermal tank top with built-in removable bra — styling detail

Infrared-reflective U-neck thermal tank top — layering detail

CatWarm U-neck thermal tank top — full look

CatWarm U-neck thermal tank top size chart — S, M, L

FAQ

Does infrared-reflective fabric actually keep you warm?

Yes — an infrared-reflective knit works by reflecting the far-infrared heat your body already gives off back toward your skin, instead of letting it escape. That lets a thin, breathable layer retain warmth without the bulk of thick fleece. It doesn't generate heat on its own; it conserves the heat you produce.

What is a removable bra pad, and how is it different from a shelf bra?

A shelf bra is just an inner band of elastic sewn into the tank — minimal support. Our tank has removable molded pads that give real shaping and coverage, and you can take them out to wash them or wear the tank without them. It's one piece instead of a tank plus a separate bra.

Can I wear this thermal tank as a top on its own?

Yes. The U-neckline, built-in bra, and full side coverage are designed so it looks finished worn solo — not just as hidden underwear. In colder weather it also layers invisibly under sweaters and jackets.

Is a thermal tank a good base layer for winter?

It's ideal as a lightweight base layer: the infrared-reflective knit adds warmth without adding bulk under your outer layers, and the smooth finish won't bunch. For very cold, active days, pair it with the matching CatWarm Thermal Leggings.

How do I choose my size?

The tank comes in S, M, and L with super-stretch fabric that holds its shape. See the size chart image on this page; if you're between sizes, size up for a looser base-layer fit or stay true-to-size for a fitted top.

How do I care for it?

Machine wash cold, gentle cycle, and lay flat or hang to dry to protect the stretch and the infrared-reflective finish. Remove the bra pads before washing if you prefer.

Also available: a deeper V-neck cut, or the sleeker Heatwave Sleek U-neck with a sewn-in bra (no removable pads).

5 stars: 338 (83%)
4 stars: 67 (17%)
3 stars: 0 (0%)
2 stars: 0 (0%)
1 star: 0 (0%)

The fabric is soft and cozy, super comfy to wear, and the style is cute. I didn’t expect this tank to be so warm too!

I bought all three colors, and they’re so comfy—soft against the skin, like wearing nothing at all, light and warm!

Perfect for sleeping in—it’s really warm. In the morning, I just throw on a jacket, and I’m good to go!

It’s really comfortable, no feeling of restriction. The square neckline is unique and has a bit of a French vibe. The fabric is soft and feels amazing!

I was pleasantly surprised when I received it! The quality is fantastic, super versatile. The tank and bra combo is so convenient—no need for a separate bra, and it really flatters my figure.

It feels great to the touch, warm and cozy, with a good amount of support without being tight. Nice! I actually prefer wearing it without the padding, but if the padding were a bit thinner, it’d be perfect.

Wearing the brown one today, no padding, and it’s so comfortable without any restrictions.

This white is gorgeous—not a stark white, but a softer, creamy off-white. It’s easy on the eyes and not see-through. It’s warm, comfortable, and the fabric is so soft. The padding is thick, not flimsy, which makes the chest look perky and sexy. Overall, it’s comfortable, warm, and stylish.

The craftsmanship is great, and the fabric is soft with a velvety feel. It’s super comfy, not chilly at all. The built-in padding is so handy—I’ll be wearing this a lot in the fall!

I washed it once before reviewing, and it didn’t lose its shape. Still as comfy as ever!

It really enhances my shape, and the exposed collarbone is eye-catching. The straps are so unique! I started with the black one, and now I’m planning to get the caramel too. Yay!

Wow~~, this tank is amazing—it’s the most comfortable one I’ve ever worn! And it’s a tank and bra in one. So many colors and styles—I’m spoilt for choice!

I love the soft, fuzzy feel of the fabric—it’s like a little pet, so comforting. I wish they had this in blue, but unfortunately, the brand doesn’t offer that color.

First, I got the black one and loved it so much that I ordered the caramel color too. Yay!

The infrared reflection thermal tank top is a winter essential! The built-in bra is so supportive, and I love not having to wear a freezing cold bra in the morning.

I am absolutely in love with this infrared reflection thermal tank top. The Japanese Hush Fiber feels like a second skin and keeps me incredibly warm.

This infrared reflection thermal tank top is the best layering piece I own. The Japanese Hush Fiber is so thin yet incredibly warm.

Absolutely obsessed with the +5¬∞C heat boost! The far-infrared thermal clothing makes my winter commute so much better.

I was skeptical about the +5¬∞C boost, but the CatWarm technology is real. This thermal base layer keeps me incredibly warm without any bulk.

This infrared reflection thermal tank top is a total game changer for my winter commute. The built-in bra offers amazing support and the +5¬∞C boost is real.

The built-in bra thermal top is perfect for winter yoga sessions. The far-infrared thermal clothing stretches well and provides excellent heat retention.

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