Space Bag

[Jonesy]

I had seen these before but really didn't have a reason for using them.

https://www.spacebag.com

Would these be useful in a BOB?

[endurance]

I've used them on my last two trips to Europe and I found them very useful at getting more into your bag without busting zippers. I bring two full mediums and empty large (as a dirty laundry bag). Since my first trip was a 22 day cycling trip in the UK and Italy in October, it was important to pack for the worst and the best of weather for both on and off the bike. There is simply no other way I could have packed enough for the type of weather I was expecting in less space. They worked great (and yes, I did laundry along the way, but having an empty space bag to hold your wet clothes after a day's ride in the British p!$$ is nice until laundry day).

Just be aware, because it compacts clothes down a great deal, your bag can become unreasonably heavy quite easy. That said, it opens up options that otherwise wouldn't work well in a typical BOB, like wool sweaters, several pair of extra socks, and bulky winter jackets.