Down jacket with no loft (warmth) - Rab Microlight Alpine Jacket - Women's

This jacket is pretty stylish and pretty well made. However, this is about the thinnest down jacket I have ever seen. Since a jackets warmth comes from the trapped air inside, the more trapped air, or loft, it has, the better. Because of the narrow and very tightly compacted baffles on this jacket, it has almost no loft. Just from looking at it, I didn't think it could provide much in the way of warmth. Compared this jacket to a Western Mountaineering Flash Jacket which actually has much less down in it (by weight), but has about 4 times as much loft. This jacket is not nearly as warm as the Flash Jacket.

Regardless of what you read in other reviews, down is not a natural insulator as many synthetic materials are. Down only provides warmth by trapping air (loft). There is no warmth in a down jacket without loft (trapped air). If you really want a thin jacket, and also want warmth, then stay away from down jackets, and get a synthetic jacket.

This review was written in the old system and had content requirements that are different than reviews written today.