The Thermarest Neo Air is the lightest non-self-inflating air mattress available & packs down to the size of a 1 litre water bottle. Thermarest have utilized 2 patent pending technologies; the Triangular Core Matrix creates an internal truss system making it far more stable than any other uninsulated air mattress, while the reflective barrier returns warmth to your body & reduces heat loss to the ground, keeping you three times warmer than any other uninsulated air mattress. Dimensions: 51x 183cm. Packed: 23x 10cm. Weight: 410g