Hybrid mapped, 8.8 oz, high warmth-to-weight ratio

We’ve been keeping an eye on Rab, and their Mythic Alpine Light Down Jacket really impresses us (shop M’s, shop W’s). Using mostly 900 fill power down, but replacing it with PrimaLoft Gold on the sides, cuffs, shoulders, and base of the hood, they have created an ultralight hybrid of supreme quality and high performance.

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• Price: $315
• Weight: 8.8 oz
• Fabric: 10D Ripstop Nylon
  
• Fill Power: 900 | Down Weight: 2.8* oz
• Percent Down Weight: 32%*
• Uncompressed Down Volume: 2520
• Down Volume/Jacket Weight: 286* in3/oz *does not count synthetic insulation
• Pros: Ultralight. High warmth-to-weight. Good value. Hybrid mapped.
• Cons: PrimaLoft Golds is less efficient than 900 fp down.

Features

This puffy weighs only 8.8 oz, 2.8 of which are down, plus an estimated .5 oz of PrimaLoft Gold used throughout, which when combined, is 38% of the garment’s mass. That’s actually the third highest total insulation-to-weight ratio on our list (not counting the parka), and means this puffy offers incredible warmth at a very low total weight.

What’s more, at $315, it’s less expensive than similar lightweight down jackets, and a great value overall. While it underperforms our top pick, the Zpacks Goose Down Jacket, it does save you $60 and that makes it well worth considering.

While we still prefer the simplicity of 100% down, the hybrid insulation does hypothetically increase the lifespan and weather resistance of this jacket in the areas that are most abused and most exposed. We have yet to test one to that extent, but look forward to trying it more this season to see if it lives up to its full potential.

Verdict

The Rab Mythic Alpine Light is a seriously excellent ultralight down jacket, and it’s got the stats to back it up.  

Check out more great ultralight puffy wear in our guide to the best down jackets and pants of the year.