Down is the soft insulating cluster material from birds such as ducks or geese. It differs from the more structured feathers that can also appear in a fill blend. Read the fill description rather than treating every feather-filled garment as identical.
Separate composition from performance
A label may describe the proportion of down and feathers, while another specification describes fill power. These measure different characteristics. Neither should be confused with the total quantity of fill in the jacket.
Inspect how the jacket holds insulation in place and which areas are filled. Hood, sleeves and torso may have different construction. A complete warmth assessment also needs coverage, fit and intended use conditions.
Ask questions that clarify the product
Request the fill composition and any stated supporting documentation. If sourcing claims matter to your purchase, ask for evidence tied to the product rather than accepting a general company statement. Keep the relevant paperwork with the order.
Consider care before buying. Down requires a suitable drying process after cleaning. If you cannot follow the garment's instructions at home, factor appropriate cleaning into the ownership decision.
Does a higher fill-power number mean the jacket is warmer?
Not by itself. Fill quantity and construction also influence warmth. Compare complete product details and your use rather than ranking every jacket by one number. A lighter high-loft design and a heavier insulated garment may be intended for different situations.
Related reading
Jacket fabric weight and GSM guide. For another useful reference, see Outdoor jacket fabric guide.
