The thermarest evolite plus has the same low bulk high loft comfort of their evolite mattress plus thermocapture technology of added warmth if yoursquore looking for the best value in ultralight backpacking mattress comfort and convenience look no further the evolite plus mattress39 patent pending airframetrade construction is the foundation using alternating channels of foam and air to combine amazing compressibility with easy self inflation and a stable high loft comfort not fou