Product reviews/11/24/2023

ISPO Award Winner 2023: Ultrasphere 4.5 by Rab

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The Ultrasphere 4.5 by Rab is a featherlight sleep mat for demanding mountain adventures. It is a contemporary product, equipped with smart details and an eco-friendly design.

New lightweight standard

When weight is a crucial factor in outdoor adventures, top-notch product quality becomes especially important. Rab's Ultrasphere 4.5 sleep mat equips adventurers with an ultralight yet warming insulating layer. In terms of warmth-to-weight ratio, this pad sets standards among lightweight products: an impressive thickness of 8 centimeters contrasts with a mere weight of 370 grams. Its R-value of 4.3 and compact packing size speak volumes. The pad's design further integrates a heat-reflective TILT lining with offset air chambers to effectively trap warmth inside. Rab also prioritizes innovative and sustainable fabrics. Thus, 100% recycled polyester outer fabric with an internal TPU coating (GRS certified) and a fluorocarbon-free DWR is used in the mat construction. “Rab is renowned for its strides in sustainability, particularly in premium ingredients,” emphasizes Luisa Smith, an ISPO textile expert. The lightweight fabrics, as well as the mummy shape of the mat, have a positive effect on the mat's overall weight. Added features such as a low-profile two-way valve for easy inflation and deflation and an included pump sack highlight the product's innovative design. Paired with Rab's Mythic Ultra 120 sleeping bag, a high-performance sleep system emerges, weighing less than 700 grams and ensuring protection even in freezing temperatures.

The Ultrashere 4.5 is not much bigger than a tennis ball
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Thoughtful design

Crafted for activities ranging from bikepacking through mountain ranges to multi-day trail running, this mat boasts a groundbreaking design that combines innovation with functionality. The outer fabric of the Ultrasphere 4.5 is a testament to Rab's commitment to sustainability and performance. A newly developed 20D recycled polyester, laminated to a lightweight, airtight TPU film, ensures durability without compromising on weight. Two layers of TILT reflective film help reduce radiant heat loss without adding weight or bulk. This combination contributes to the mat's remarkable warmth-to-weight ratio, making it an ideal choice for demanding conditions.

Portability is a key consideration for adventurers, and the Ultrasphere 4.5 doesn't disappoint. With a packed size of 18x9cm, it fits seamlessly into any backpack. The low-profile two-way valve facilitates easy inflation and deflation, while the soft-touch embossing replaces traditional printing, saving additional weight. Rab understands also the importance of rapid and hygienic inflation and thus includes a pump sack with the Ultrasphere 4.5. This thoughtful addition, along with the roll-away stuff sack containing a repair kit, ensures that adventurers can focus on their journey without worrying about equipment failures. Rab's commitment to environmental and social responsibility is evident in their approach to challenges both in the outdoors and in the world at large. As part of Equip Outdoor Technologies Ltd., Rab strives to apply lessons learned in the wilderness to address global issues, from climate change to fairness and opportunity for all. The Ultrasphere 4.5 is a tangible expression of this ethos.

With a pump bag, the mat can be inflated hygienically as well as preventing mold.
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Multi-useability in mind

In combination with Rab's Mythic Ultra 120 MB sleeping bag, the lightest down sleeping bag the brand has ever created, the Ultrasphere 4.5 forms a high-performance sleep system weighing less than 700g. Together, they provide uncompromising protection and comfort in temperatures as low as zero degrees. Alternatively, the Ultrasphere 4.5 stands strong as an individual sleeping mat, representing Rab's lightest option in their sleeping mat range. Not compromising on comfort and performance, it's the ideal foundation for bikepacking, multi-day mountain runs, or lightweight alpine missions.

The Ultraspehere 4.5 can be packed super compact.
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What the ISPO Award jury says:

"Remarkably lightweight: With the Ultrasphere 4.5 Rab has crafted a sleep mat that sets innovative and contemporary product highlights. Despite its ultralight design, consumers receive a sturdy and reliable insulating lining without compromising comfort, warmth or protection. The sustainable material features further enhance the overall positive impression."
ISPO Award Jury

These features convinced the Jury:

  • Made of 100% recycled polyester (GRS certified)
  • R-Value: 4.3
  • Lightweight
  • Thermal regulating

Product Specifications:

  • Weight: 370 g
  • Available: Spring/Summer 2024 (not US & DE)
  • RRP: € 180.00 (£ 180.00)
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