REI AirRail 1.5 Self-Inflating Sleeping Pad

This is one of the new REI foam-hybrid self-inflating pads for backpackers. The 2.5-inch air and PrimaLoft filled side tubes cradle sleepers and give a sense of being stabilized on the pad to prevent rolling off. The center features a lightweight, compressible, cross-core foam insulation that supports body weight well without the feeling of sleeping on an air mattress.

The foam center is “self-inflating,” which means this REI sleeping pad will inflate without your air power when the valve is open. It features a nice weight saving tapered shape, a little less extreme than “mummy” shape, but still saving some material, weight and pack size none the less. This pad also has a nice durable and slip resistant nylon outer shell, which passed our durability tests with ease. It’s got a slightly re-enforced bottom and non-slip top, which is great.

It’s not the lightest pad or most feature-laden pad on the market, but for fans of REI and their in-house brand of products, this is a good buy and a good bet for a normal summer backpacking adventure.

Universal Attributes

Performance: 5
This sleeping pad gets a performance rating above average because it’s a tried and true, affordable and functional design without restricting end use. It’s light enough to backpack with yet durable and stable enough for family use. The high-flow valve really does work well on both inflation and deflation.

Design: 3.5
It’s a solid design, a very fine design, but nothing superior or innovative about it. The tapered shape leaves plenty of space for sleeping in all positions and isn’t restrictive or minimalist like a true mummy pad can be. It’s a more universal pad in unisex sizes, and also available in Long and Long Wide.

Durability: 4
The nylon REI uses is quite durable indeed. Because this isn’t meant to be the lightest pad on the market; you can get a little bit more durability in your fabrics with other pads.

Innovation: 3
It’s fairly innovative to add insulation to the 2.5-inch side tubes, especially for a bag of this price point. It captures warmth around the body and keeps you in place during the night. They’re a visceral clue as to where you are on your pad if you are tossing and turning in an unfamiliar environment.

Features: 3
The best feature of this bag is the insulated side tubes. The foam center floor with cross-core perforation has great R-value, but is heavier than just an air-filled pad. It also allows for self-inflation, which requires fewer breaths to fill.

Universal Tests

Comfort test: Some testers find the foam floor comfortable as you sleep flatter and lower to the ground, but without the elevation and bounce of an “air mattress.” You’re less likely to roll off this pad because it’s just a sheet of perforated foam with a little bit of air in it, not to mention the side chambers that act as bumpers and lock you into place.

Weighted overnight test: REI’s self-inflating pad and valve passed with issues, holding its air overnight.

Durability test: Passed the test, standing up to a beat from large dogs and the rocky ground without issue.

Re-pack test: Fell a little bit short here as the stuff sack is just barely big enough for the packed pad, even right out of the box, and the included compression strap is pretty much required, not optional.

Inflation speed test: Despite it being “self-inflating,” it still required about 15 big breaths to inflate the pad and its side tubes on first use. However, after a few uses, the self-inflation really does work. If you roll it out and open up the valve, the foam base will inflate. So if you’re really tired or winded, and don’t care about the side tubes, then save your breath.

Packed size test: At 1 pound, 10 ounces, the pad packs down to a very reasonable size, about the size of a square football, which is plenty small for backpacking, bike packing, adventure travel, or other human-powered activities.