The Cosmic SI is a self inflating sleeping mat that works well for three season use. Simple, effective, great value and generously sized.
The perfect pairing with any of Kelty's backpacking bags.
Kelty's Cosmic SI Mummy Sleeping Mat is a large self inflating mat with a good R-Value that means it can be used for three season camping. It has a generous length and width to keep you comfortable and a good level of insulation too.
As with all self inflating mats, the weight and particularly the pack size, are not going to suit everyone as both are heavier and larger than many alternatives. However, this is a really nice package with 20D material providing a durable base and a solid, reliable valve. This is combined with a very reasonable price for a mat like this.
- Reviewed by BasecampGear
From 2020, there is a new industry standard for measuring the R-value (level of insulation) of sleeping mats – ASTM F3340-18. This new standard is the sleeping mat equivalent to the EN rating for sleeping bags.
You can now directly compare the R-value of mats rated using the ASTM F3340-18 with confidence that is a fair and accurate comparison between mats. In simple terms, the higher the R-value, the warmer the mat.
In general terms, an R-value below 2.0 is for summer use, 2.0 to 4.0 is for cooler 3 season use and 4.0+ is for winter temperatures. This will be also be dependent on your sleeping bag, how cold you sleep etc. Please contact our customer service team if you need advice on choosing the right mat for your activity.