Manufacturer:
The Rab Ionosphere 5.5 insulated air mat delivers exceptional winter warmth with an R-value of 5.5 and advanced TILT reflective technology. Featuring Stratus™ R insulation and an 8cm thickness, it reduces radiant and convective heat loss in sub-zero conditions. Lightweight and compact, it’s ideal for mountaineering, ski touring and winter fast-packing. Engineered for maximum warmth-to-weight efficiency in demanding alpine environments.

All variants out of stock


The Rab Ionosphere 5.5 is a high-performance insulated sleeping mat engineered for winter mountaineering, ski touring and cold-weather fastpacking. Designed for hostile alpine environments where minimal kit is essential, it delivers exceptional warmth-to-weight performance with an R-value of 5.5. Featuring TILT reflective technology to reduce radiant heat loss and Stratus™ R insulation to limit convective heat transfer, it maximises thermal efficiency on frozen ground and exposed bivi ledges. The 8cm thickness ensures comfort and ground separation, while the tapered mummy profile reduces excess bulk without compromising support. Lightweight, compact and highly packable, it is optimised for multi-day winter objectives.

Features:
TILT reflective lining reduces radiant heat loss
Stratus™ R insulation traps air to minimise convection
8cm thickness for enhanced comfort + insulation
20D soft-touch upper fabric
Durable 30D base for rough ground protection
Oversized outer chambers keep you centred on the mat
Tapered mummy shape for weight efficiency
Low-profile two-way valve for rapid inflation/deflation
Pump sack included
Roll-away stuff sack and repair kit included

Specifications:
Weight (regular): 615g / 21.7oz 
Shape: Tapered Mummy
Thickness: 8cm
Insulation: Stratus™ R
R-value: 5.5
Activities: Camping, Trekking, Mountaineering

Regular:
Dimensions: 183cm x 51cm x 8cm
Packed Size: 24cm x 12cm (9.4in x 4.7in)

Long Wide:
Dimensions: 196cm x 64cm x 8cm
Packed Size: 29cm x 14cm (11.4in x 5.5in)

*
*
*
*
*

The Rab Ionosphere 5.5 is a high-performance insulated sleeping mat engineered for winter mountaineering, ski touring and cold-weather fastpacking. Designed for hostile alpine environments where minimal kit is essential, it delivers exceptional warmth-to-weight performance with an R-value of 5.5. Featuring TILT reflective technology to reduce radiant heat loss and Stratus™ R insulation to limit convective heat transfer, it maximises thermal efficiency on frozen ground and exposed bivi ledges. The 8cm thickness ensures comfort and ground separation, while the tapered mummy profile reduces excess bulk without compromising support. Lightweight, compact and highly packable, it is optimised for multi-day winter objectives.

Features:
TILT reflective lining reduces radiant heat loss
Stratus™ R insulation traps air to minimise convection
8cm thickness for enhanced comfort + insulation
20D soft-touch upper fabric
Durable 30D base for rough ground protection
Oversized outer chambers keep you centred on the mat
Tapered mummy shape for weight efficiency
Low-profile two-way valve for rapid inflation/deflation
Pump sack included
Roll-away stuff sack and repair kit included

Specifications:
Weight (regular): 615g / 21.7oz 
Shape: Tapered Mummy
Thickness: 8cm
Insulation: Stratus™ R
R-value: 5.5
Activities: Camping, Trekking, Mountaineering

Regular:
Dimensions: 183cm x 51cm x 8cm
Packed Size: 24cm x 12cm (9.4in x 4.7in)

Long Wide:
Dimensions: 196cm x 64cm x 8cm
Packed Size: 29cm x 14cm (11.4in x 5.5in)

Product reviews
*
*

Discount Codes

If you are a member of an outdoor or watersports group and have a discount code, please enter it in the box below.

Click here for more information on discount codes