The Western Mountaineering Alpinlite sleeping bag delivers ultralight comfort for three-season adventures. Rated at 20°F (-7°C), this Extreme Light series bag boasts exceptional warmth-to-weight thanks to its 850+ fill power Polish goose down (claimed 900+ fill power) and lightweight, durable shell fabric. Factory overfilled by approximately 10%, the Alpinlite offers increased loft and insulation stability, exceeding its rated temperature performance. Its generous dimensions provide ample room for movement, surpassing the snugger fit of comparable models.This review delves into the Alpinlite's performance in real-world conditions, examining its warmth, comfort, and construction details. We explore the benefits of its roomy design, high-quality zipper, and effective down-filled neck collar. A comparison with the Verselite highlights the Alpinlite's trade-off between spaciousness and ultralight efficiency. Ultimately, we assess whether the Alpinlite's premium price tag is justified by its superior performance and longevity for serious adventurers prioritizing comfort and reliable warmth.
Pros And Cons
- Extremely light outer shell fabric (0.9 oz per square yard)
- 12 denier mini ripstop fabric with DWR spray finish
- Filled with 21 ounces of 850+ fill power Polish goose down (claimed to be 900+ fill power)
- 5 1/2 inch loft (increased to 5 3/4 - 6 inches due to overfill)
- Overfill adds warmth (approximately 5°F reduction in lowest temperature rating)
- Full down neck collar
- Roomier than the Verselite (2 inches greater circumference at shoulders and waist)
- Number 5 YKK coil zipper with Dacron stiffener tape to prevent snagging
- Nylon taffeta interior fabric
- Comes with stuff sack and storage sack
- Overfill adds weight, may not be ideal for ultralight backpacking
- Roomier design may be less efficient in cold temperatures due to dead air space
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Alpinlite: An Overview of Features
The Western Mountaineering Alpinlite is a 20°F (-7°C) rated sleeping bag from their Extreme Light series. This translates to exceptional lightweight performance thanks to the ultralight 0.9 oz/sq yd 12 denier mini-ripstop shell fabric with a durable water repellent (DWR) finish. The bag features 21 ounces of 850+ fill power Polish goose down (claimed to be 900+ fill power).
This model is factory overfilled by approximately 10%, resulting in added warmth and loft. The overfill is clearly marked on the bag's tag. The increased down fill improves insulation stability, preventing down shifting during sleep and potentially lowering the temperature rating by 5°F (from a rated 20°F to approximately 15°F).
Loft and Dimensions: Roomy Comfort
The Alpinlite boasts a stated loft of 5 1/2 inches, but with the overfill, the actual loft measures closer to 5 3/4 to 6 inches. This provides generous insulation and comfort. The bag's dimensions are considerable: 64 inches of shoulder circumference, 55 inches at the waist, and 39 inches at the footbox.
This translates into a roomier sleeping experience than comparable bags, like the Verselite, which features a smaller circumference. The increased space enhances comfort, especially for individuals who prefer more freedom of movement during sleep. However, this roominess might slightly impact the efficiency of insulation due to increased dead air space.
Field Test and Temperature Performance
A field test in colder-than-rated temperatures (9.5°F) with the Verselite sleeping bag indicated that Western Mountaineering's temperature ratings might be conservative. The Alpinlite's 20°F rating, with the overfill, should provide comfortable sleep even in temperatures as low as 15°F or even lower, based on the reviewer's experience. The reviewer's plan is to further test the Alpinlite in expected 13°F conditions in the mountains.
This suggests a high level of warmth and insulation, providing confidence in its ability to handle unexpected drops in temperature during outdoor adventures. The increased down fill clearly contributes to superior cold weather performance, surpassing the manufacturer's stated ratings.
Zipper, Fabrics, and Design Details
The Alpinlite features a #5 YKK coil zipper with Dacron stiffener tape to prevent snagging. The inner fabric is a nylon taffeta, while the outer is a 12-denier ripstop. This combination ensures smooth zipper function and durability. This is supported by the reviewer's experience of never having issues with the zippers.
A key feature is the full-length down-filled neck collar, secured with Velcro and a drawstring. This collar effectively seals in warmth, maintaining a comfortable interior temperature while preventing cold air from entering. It provides exceptional insulation and warmth. The bag is available in a right or left zip and in cranberry color.
Comparison and Conclusion
The Alpinlite, while similar in weight to the Verselite (around 1 lb 15 oz), offers more interior space (especially at the shoulders and waist), making it a roomier and less restrictive option. This increased roominess comes at the cost of slight insulation efficiency compared to the Verselite, as more air needs to be heated. The Alpinlite is better suited for three-season use, providing excellent warmth and comfort for average-sized individuals.
Western Mountaineering's reputation for high-quality, durable sleeping bags is well-deserved. The Alpinlite, with its superior down fill, robust construction, and thoughtful design features, exemplifies their commitment to excellence. While it's a pricier investment, its durability and exceptional performance make it a worthwhile purchase for serious adventurers who prioritize lightweight comfort and long-lasting reliability. The choice between Alpinlite and Verselite depends on individual preferences for spaciousness versus ultimate ultralight weight.
