Polartec Alpha Direct Quilt Liner
The quilt liner that warms on cold nights and breathes on hot ones — dumping moisture vapor as fast as your body makes it. Always cuddly, never clammy.
Add a soft, breathable layer to your sleeping bag or quilt, or use it on its own on warm nights. Made in Pennsylvania, the Polartec Alpha Direct Quilt Liner measures 72 × 55 inches, with a sewn-in foot box to keep your feet tucked in. Choose from three fabric weights, from 7 to 12 oz.
Choose your fabric
Not sure which fabric to choose? Start with standard Alpha 90 for a balance of weight and durability.
- Alpha 90 · 8 oz: The all-around choice for regular use.
- Alpha Trail 90 · 7 oz: Our lightest option. More delicate than standard Alpha 90, best for those who prioritize minimum weight and handle their gear carefully.
- Alpha 120 · 12 oz: The warmer option for cooler nights or extra insulation in your sleep system.
What makes it different
Polartec Alpha Direct skips the shell fabric entirely — the insulation is the surface, designed to sit directly against your skin. That means less bulk, faster drying, and a next-to-skin softness you won’t find in a standard sleeping bag liner. Unlike other fabrics that go clammy when temperatures and humidity climb, Alpha Direct stays soft and dry against your skin — no sticking, no cling, no matter how muggy it gets. Use it as a standalone summer quilt on warm nights, a versatile camping liner for any sleep system, or a packable backpacking liner that pulls its weight on thru-hikes, weekend trips, and nights at home alike. Trail Tested. Couch Approved.
Sewn-in foot box
This is not a flat rectangle. The liner is 72" long × 55" wide, with a 15" circular foot box sewn in at the bottom, so your feet tuck into a closed end.
How to use it
- As a sleeping bag liner: Adds 5–15°F to any 3-season bag, extending your system deep into shoulder season
- As a quilt liner: Pairs with any backpacking quilt to extend its warmth range without the bulk of a heavier bag
- As a summer quilt: Standalone warmth rated to 50–60°F — ultralight, packable, ready for warm-weather camping
- For backpacking and thru-hiking: At 7–12 oz and packing down to a 10" × 4" cylinder, it earns every gram without adding bulk to your kit
Comfort and weight
| Model | Weight | Standalone Comfort | As a Liner Adds |
|---|---|---|---|
| Alpha Direct 90 | 8 oz | ~60°F | 5–10°F |
| Alpha Trail 90* | 7 oz | ~60°F | 5–10°F |
| Alpha Direct 120 | 12 oz | ~50°F | 10–15°F |
*Alpha Trail 90 has two-way stretch; Alpha 90 and Alpha 120 have four-way stretch. Trail 90 packs even smaller than Alpha 90, but it is more fragile and prioritizes weight savings over durability.
Want to push your liner into shoulder-season territory? Add the Windproof Shell — 2.9 oz of 10 denier nylon that blocks wind and light moisture, extends your effective warmth range by several degrees, and packs down to nothing.
Want that warmth-and-wind combo in one sewn quilt? The Wind Gap Alpha sews Alpha Direct to a 20 denier nylon windproof shell — a windproof liner, 50°F top quilt, or hammock underquilt in a single piece.
Specs
| Weight | 7 / 8 / 12 oz |
|---|---|
| Length | 72.0 in (1.83 m) |
| Width | 55.0 in (1.4 m) |
| Temperature rating | 50–60°F standalone · adds 5–15°F |
| Shell | Polartec Alpha Direct (no shell fabric) |
| Features | Trail 90: 7 oz · Alpha 90: 8 oz · Alpha 120: 12 oz · adds 5–15°F to any bag or quilt |
| Made in | Hulmeville, Pennsylvania, USA |