Rab/Ultrasphere 4.5 Wide Long Sleep Mat

The Optimal Choice for Minimalists



Rab is a brand founded in 1981 by British climber Robert Carrington, producing highly reliable, high-quality gear for extreme cold environments and alpine climbing worldwide. The brand is especially renowned for its expertise and meticulous attention to detail in down and syntheticinsulation products, which are deeply rooted in its heritage.

The Ultrasphere 4.5 is a feather-light air mat that combines the ultra-lightweight TILT fabric with an offset baffle construction that retains heat. Weighing just 505g, with impressive performance (R-value 4.3) and a pack size minimized to 19×9cm, it is truly the optimal solution for minimalists. Many users have found the regular size to be somewhat small; the Wide Long version is approximately 13cm wider than the regular, making it the best choice for those prioritizing sleeping comfort.

The newly developed tapered mummy shape pursues a balance between ultra-lightweight and high performance. By alternating the position of the holes between horizontally arranged airbaffles, internal air convection is greatly reduced, providing outstanding warmth. Body pressure is evenly distributed, and its 8cm thickness ensures a very comfortable sleeping experience. Inside, special dual-layer TILT reflective film (Thermo Ionic Lining Technology), made from metallic materials, reflects heat emitted from the body, greatly minimizing radiant heat loss. This allows for a reduction in the structure needed for consistent warmth, achieving a remarkable balance of weight and thermal efficiency. The soft-touch fabric minimizes sleeping bag slippage. Equippedwith a low-profile, dual-direction valve and a large included pump sack, the mat can be inflatedquickly, and the side-opening stuff sack ensures easy packing and unpacking. Thanks to its tapered mummy shape, pairing it with the Insulation Sheet 00 can help reduce condensation on sleeping bags that extend beyond the mat, while also boosting insulation, making it possible tostay even lighter and more comfortable in the outdoors.


- R- VALUE 4.3
- 20D recycled polyester with TPU coating
- Fluorocarbon-free DWR durable water repellent finish
- Equipped with a special two-layer TILT reflective film derived from metal, it reflects the heat emitted from the body, significantly reducing radiant heat loss
- The unique structure of the lightweight mat, with the holes in the chamber partitions offset, significantly reduces air convection inside the mat and maintains warm air
- Tapered mummy shape for lightweight fit
- Low profile 2-way valve for easy inflation and deflation
- Pump sack included
- Repair kit included
- Includes rollaway stuff sack
- Light gray color
- Rab domestic genuine product


Size: 196 x 64 x 8cm (Regular 183 x 51 x 8cm)
Pack size: 19 x 9 x 9cm (regular 18 x 9 x 9cm)
Weight: 505g (regular 370g)
R-VALUE : 4.3
Material: Fabric: 20 denier recycled polyester with TPU coating
Includes: stuff sack, pump sack, repair kit

*The image is regular size.



Product code 09965-43-400