Therm-a-Rest ProLite Series Pads

The ProLite 4 at Camp Muir
The ProLite 4 at Camp Muir

Every once in a while a piece of gear comes along that is unanimously considered to be indespensible. Kyle’s insulated sleeping pad of choice, the ProLite 4 from Therm-a-Rest (recently replaced in their line by the equally innovative ProLite Plus), is one such item. For years, Thermarest has led the market for backcountry sleeping pads, and their weight-to-warmth ratios remain unmatched by other manufacturers. Patented insulating technology and superior design prompt countless reviewers to tend toward the superlative, whether they’re calling Therm-a-Rest’s design team “impossibly ingenious,” or touting its products as pieces of “engineered masterpiece.” Regardless, the industry’s positive response to Therm-a-Rest’s lightest four-season mattress is born of both a tried and true comparison of warmth to weight ratios, and the pad’s simple, and classically user-friendly feel.

As with any type of gear, buying your sleeping pad is typically an exercise in tradeoffs. Generally, the warmer the pad, the heavier it will be. Enter Therm-a-Rest’s “fast and light” series, which tries to strike the perfect balance between insulating pads and feather-weight gear. Their ProLite pads tend to achieve this aim with style to spare.

Sleeping pads’ ability to retain and transfer heat is rated by an industry standard known as the “R Value.” Essentially, the higher this number, the warmer you’ll be. The ProLite 4, for example, has an R value of 3.2. For comparison’s sake, it’s successor, the ProLite Plus, boasts an R value of 3.8, and the women’s version of the same pad clocks in with an R Value of 4.6. Each of these pads weigh in at about a pound and a half, depending upon the length you purchase. The ProLite 4 was the warmest lightweight pad for taller people (like Kyle) on the market last year.

Regardless, this pad (or one of its similar successors in the ProLite series) is top of the line. If you’re short enough and a colder sleeper (people’s varrying nighttime metabolisms also contribute to their sleeping system warmth needs), you can buy the women’s version like this guy did, which has added heat retention technology in the core section, and therefore, a better warmth-to-weight ratio than the men’s. To help you sort through the available models and lengths, please see our comparison chart, below:

Model Name Size-  Length & Width Weight R Value
Shop for it
ProLite 4 (2008) Small- 48″ x 20″ 1 lb, 1 oz 3.2 Gear for Adventure
ProLite 4 (2008) Regular- 71″ x 20″ 1 lb, 8 oz 3.2 Gear for Adventure
ProLite 4 (2008) Large- 78″ x 20″ 2 lbs, 1 oz 3.2 Gear for Adventure
ProLite 4- Women’s (2008) Regular- 66″ x 20″ 1 lb, 8 oz 3.5 Whitaker Mountaineering
ProLite Plus (2009) Small- 47″ x 20″ 1 lb, 1 oz 3.8 Backcountry.com
ProLite Plus (2009) Regular-  72″ x 20″ 1 lb, 8 oz 3.8 Backcountry.com
ProLite Plus (2009) Large- 77″ x 20″ 2 lbs, 1 oz 3.8 Backcountry.com
ProLite Plus- Women’s  (2009) Regular- 66″ x 20″ 1 lb, 8 oz 4.6 Backcountry.com

User friendly design details include the “self-inflating” air valve, and a very durable outer layer, not prone to leaks or breakages. In the unlikely event that your pad does break down, remember that it comes with a lifetime warranty.

Finally, people love these pads because they are incredibly comfortable. This guy perhaps goes a little bit overboard when trying to convey what a great night’s rest you’ll get, but there’s a reason these pads make people crazy in a good way. Whether its inch of insulation is the only thing between you and snow at 10,000′ or you’re sleeping on volcanic rock near sea level, this pad is astoundingly comfy, warm, and lightweight.

  • Best for: Touring or adventure racing, where both weight and warmth are serious considerations. The fact that it’s super comfortable is just an added bonus!
  • Specs: Please see comparison chart above. Most pads pack to about 11″ x 4,” depending on the length.
  • Awards & Reviews: are countless. For a sample, check out Alpinist’s Mountain Standard Nearly Perfect Rating, Outdoor Adventure Canada’s Glowing Review, and CampSaver’s consolidation of reviews from various retailers and members of the general public.