The quality of a down sleeping bag is primarily determined by the down fill used to make the bag. The most common commercial down is derived from geese instead of ducks. Typical down fills used in sleeping bags range from 500 and 800. The higher the number, the better the quality. The key issues impacted by down quality are warmth and durability. Higher-grade down offers more warmth for the weight.
High-grade down is also more durable over time. It recovers its loft faster after being compressed, and it can be compressed more times before it loses it loft. The durability issue can be significant, with high-grade down bags lasting years longer than lower-grade down bags.
A quality sleeping bag will be supplied with a separate storage bag that should be used any time the bag is not in use. Storing a down sleeping bag correctly will extend its life.
Always remember that down bags lose their loft when wet. Backpackers must take great care to ensure their bags stay dry on trips.
A good down sleeping bag will last for years, will be lighter and outperform synthetic bags.
Article Written By A. Lee Lang
With a graduate education in both science and business, A. Lee Lang has been involved with search and rescue for nearly 20 years. Additionally, he has experience with the emergency services field and has recently been appointed as the SAR Editor for "Technical Rescue Magazine."