4.9/5 ⭐ +10,000 Happy Customers

Discover the Ready-to-Wear Hot-Water Bottle by Foundly

Designed to keep you warm and cozy during your daily routines.

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Sold Out Again & Again

Discover why our wearable Hot-Water Bottle keeps selling out.

✓ Wearable & Hands-Free

Drape it on your belly, neck, or hips.

✓ Lightweight & Practical

Lightweight at just 200g, the Urban Cross Bottle is designed for daily comfort. With an 800ml capacity, fill up to two-thirds for safe handling.

✓ Warm & Cold Usage

Long-lasting comfort: Enjoy up to 6 hours of warmth or up to 11 hours of cooling relief with the Foundly hot-water bottle – designed for every season.

✓ Highest safety standards

Designed for safety and durability, meeting international standards (BS 1970:2012) with tested elasticity, pressure resistance, and heat protection. A secure closure and large funnel ensure easy, spill-free filling.

✓ Wearable & Hands-Free

Drape it on your belly, neck, or hips.

✓ Free of toxins

 Ensuring a safe experience.

✓ Lightweight & Practical

Lightweight at just 200g, the Urban Cross Bottle is designed for daily comfort. With an 800ml capacity, fill up to two-thirds for safe handling.

✓ Warm & Cold Usage

Long-lasting comfort: Enjoy up to 6 hours of warmth or up to 11 hours of cooling relief with the Foundly hot-water bottle – designed for every season.

✓ Fair Rubber certified:

With every bottle sold, a fair trade premium goes to rubber tappers and plantation farmers.

✓ Natural Rubber

Harvested from rubber trees through environmentally friendly farming practices.

✓ Natural warmth

Made from 100% natural rubber, the Urban Cross Bottle delivers traditional warmth without electricity, cables, or EMF—just pure, natural heat.

✓ Comfy & Ergonomic

Ergonomically shaped, fitted with tactile massage ridges,boasting a relaxing soft-touch feel.

✓ Highest safety standards

Designed for safety and durability, meeting international standards (BS 1970:2012) with tested elasticity, pressure resistance, and heat protection. A secure closure and large funnel ensure easy, spill-free filling.

✓ Free of toxins

 Ensuring a safe experience.

✓ Fair Rubber certified:

With every bottle sold, a fair trade premium goes to rubber tappers and plantation farmers.

✓ Natural Rubber

Harvested from rubber trees through environmentally friendly farming practices.

✓ Natural warmth

Made from 100% natural rubber, the Urban Cross Bottle delivers traditional warmth without electricity, cables, or EMF—just pure, natural heat.

✓ Comfy & Ergonomic

Ergonomically shaped, fitted with tactile massage ridges,boasting a relaxing soft-touch feel.

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Your Questions, Answered

Can a Hot-Water Bottle ease pain?

Studies have proven that heat in general has a similar effect to a painkiller, effectively “deactivating” pain at a molecular level. In this way, completely naturally and without any chemicals, heat shuts down the regular pain response and helps with issues such as menstrual pain, neck tension, and abdominal cramps, and even diseases such as endometriosis or Crohn’s disease. However, hot-water bottles by themselves do not ease pain. UCB does not claim the capability of a medical device. In case of doubt, consult your doctor or pharmacist.

Are there any scientifically proven results about the benefits of heat?

Yes. The fact that heat relieves abdominal pain, such as colic or menstrual pain, has been scientifically proven by a UCL (University College London) scientist. Dr. Brian King, of the UCL Department of Physiology, led the research that found the molecular basis for the long-standing theory that heat provides relief from internal pains. For more information visit: Uniersity College London

How do you ensure the safety and durability of your hot water bottles?

Our Hot-Water Bottle is developed according to international safety standards, including the British Safety Standard (BS 1970:2012), ensuring durability, leak protection, and heat resistance. The high-quality material undergoes rigorous testing for elasticity, pressure resistance, and aging to prevent cracks or deformation. A secure closure system and an extra-large funnel make filling safer and easier, minimizing the risk of spills. Certified, Foundly prioritizes both comfort and safety—so you can enjoy warmth with peace of mind.

Which belt size is right for me?

Currently, we have 2 belt sizes available in our shop. Size 1 has a length of 110cm and is designed for clothing sizes S/M. Size 2 has a length of 125cm and is designed for clothing sizes M/L.

How does Foundly support fair trade and sustainable rubber farming?

With every Urban Cross Bottle sold, a fair trade premium directly supports rubber tappers and plantation farmers, ensuring fair wages, better working conditions, and sustainable farming practices.

As a proud partner of Fair Rubber e.V. (fairrubber.org), Foundly is committed to ethical sourcing. The Fair Rubber certification guarantees that the natural rubber used in our products is harvested under socially and environmentally responsible conditions. This initiative helps fund healthcare, education, and community development projects for rubber-producing communities.

By choosing Foundly, you're not just investing in high-quality, sustainable warmth—you're actively supporting fair trade and a better future for rubber farmers worldwide

What makes the Foundly Hot-Water Bottle unique?

The Foundly Hot-Water Bottle is the upgraded version of the conventional Hot-water bottle. Ergonomically shaped (including massage riffles) and designed to keep you warm and cosy during your daily routines – whether it’s at the office, during outdoor activities or while having a relaxing rest at home. In combination with our comfy, removable belt, our hot-water bottle can be worn in multiple ways: around your neck and shoulders, around your upper or lower back or around your belly

Join the comfort club today

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