Therm-a-Rest Antares (2013)

A design that’s likely to polarise users, the revolutionary system used in the Therm-a-Rest Antares dispenses with insulation on the base of the sleeping bag, and instead features straps into which a sleeping mat (any will do, but preferably a Therm-a-Rest, naturally) slides, providing the insulation underneath. The result is an application of logic (down that is squashed flat underneath you does little to insulate, so why have it?) and the bonus of being held in place while you sleep, as opposed to rolling off your sleeping mat. Not everyone will like this – especially fidgety sleepers. You can still move around in the bag, but the bag can’t move around on the mat, so your appreciation will depend on your preferred sleeping position. It’s a little heavy considering it’s stripped of underside insulation, but Therm-a-Rest claims the 405g of down fill (at least 100g more than most in our test, excluding the Terra Nova, which has 375g) has been redistributed around the bag, which – when used with a sleeping mat – will push the warmth of this sleeping bag higher than most. Nice touches include a zipped pocket near the head, ties on the main zips and a comfortable inner. 


Weight (with stuffsack) 888g (912g)
Size 203x76cm
Packed size 31x17cm
Outer fabric nylon ripstop with DWR
Inner fabric 100% nylon
Insulation 750+ fill goose down
Construction baffled/zoned insulation
Lower comfort limit 1 deg C (with airmat)
Extreme temp rating -22 deg C (with airmat)



If the Therm-a-Rest Antares works for you, it will work really well – and it’s terrific, market-leading quality at a great price. But it’s a bulky option compared to many.

Review by Simon Ingram
First published in Trail magazine August 2013