Therm-a-Rest ProLite™ Apex™

The ProLite Apex is the upgraded version of the standard ProLite, using StrataCore construction to push the R-value to 3.8 and the thickness to 5.1 cm — enough insulation for three to four seasons, including cooler spring and autumn nights, though not for deep winter. That extra warmth and comfort comes at a weight cost: the Regular size (183 × 51 cm) weighs 620 g, nearly double the base ProLite, packing down to 28 × 17 cm. Top and bottom fabric is 50D printed polyester, the WingLock valve gives fast inflation without a pump, and the self-inflating foam core still tops itself off without much manual effort. A stuff sack is included, and the manufacturer backs the material with a 99-year warranty. The Apex suits hikers who find the base ProLite thermally insufficient but don't want to jump to a heavier, pricier dedicated winter pad — it sits at a sensible midpoint between comfort, insulation, and packed weight.