Sea to Summit releases its ‘warmest ever’ sleeping mat

Sea to Summit’s latest mat, the Etherlight XT Extreme, is the thickest and warmest the company has ever made. With an R- value of over 6 it should be warm at -30°C, whilst the 10cm thickness makes it very comfortable. The mat features Sea to Summit’s air-sprung cells, which deform independently to allow the mat to conform to your body shape. The cells are filled with dual-density layers of Thermolite insulation for warmth. There are men’s and women’s versions, the latter being wider at the hip and narrower at the shoulder and having a higher R-value of 6.3. Weights are 720g for the Regular length and 950g for the Large. The Etherlight XT Extreme costs £200. seatosummit.com