Buy A Good Down Jacket: How To

While fill power tells you the quality , fill weight tells you the quantity of down. A jacket with high fill power but very low fill weight (like an ultralight layer) may be less warm than a heavy "parka" with a lower fill power.

Look for a high ratio of down clusters to feathers. A 90/10 ratio is considered premium and offers the best insulation and packability. 2. Check the Construction How the jacket is sewn determines how well it traps heat: how to buy a good down jacket

The performance of a down jacket is primarily determined by two key metrics: While fill power tells you the quality ,

Uses internal fabric walls to allow the down to loft fully, eliminating cold spots. These are warmer but bulkier. A 90/10 ratio is considered premium and offers

These are the stitched compartments that hold the down.

Premium, expedition-level quality providing maximum warmth with minimal weight and high compressibility.

A "good" jacket should include functional details that enhance its performance: Down Clothing Buying Guide - Mountain Equipment