Always on the lookout for something bigger and better? Look no further than the Therm-a-Rest MondoKing 3D Self-Inflating Foam Camping Mattress. Simply put, the MondoKing 3D is the biggest Therm-a-Rest mattress ever. Vertical sidewalls create 20% more usable sleep surface so campers have room to sleep like starfish. Dual valves allow compressible foam core to expand and inflate quickly when unpacked and only requires a few breaths for ideal firmness. Vertical sidewalls maximize the useable sleep surface and 4 inches of stabilized loft provides the comfort of home anywhere. Supple stretch-knit fabric offers deluxe breathability and a plush surface while foam core delivers all-season warmth, boasting an R-value of 11.4 (R-value measures the material’s ability to insulate; the higher the R-value, the warmer the sleeping pad). The MondoKing 3D also mates perfectly with other Therm-a-Rest 3D mattresses. The Therm-a-Rest MondoKing 3D is available in 2 sizes: Large measures 72 x 25 x 4 inches, packs to 26 x 9 inches and weighs 5 pounds 8 ounces; XXL measures 80 x 30 x 4 inches, packs down to 31 x 9 inches and weighs 6 pounds 12 ounces. Stuff sack included. Limited lifetime warranty. Made in the USA.