For sale is a brand new, never-used down sleeping bag by Sierra Designs: the ‘Women's Mobile Mummy 800 / 30F’. I purchased this for my partner whilst I was in the US, with the view of using it for 3-season backpacking here, but she decided it wasn’t going to be warm enough now that we’re moving to Canberra. Selling for $275 + postage.
You can find more information here: https://sierradesigns.com/womens-mobile ... 30-degree/
The bag uses high loft, 800 fill-power down, and should keep even cold sleepers warm to just below freezing. It’s very light for its warmth at a hair over 800 grams. One of the great features of the back is that there are slots which allow you to stick your arms out the sides; these close to prevent drafts when you’re sleeping. Combined with the ¾ centre zip, you can use the bag like a down jacket for extra warmth around camp. The packed size below is uncompressed and compared to a 1L bottle. It can easily be compressed to half of this size or smaller.