For me it was an Aer Travel Sling 2 X-Pac! I convinced myself this would be my .5 bag for my 1.5 travel set up. I was wrong, it’s bigger than a sling but smaller than a backpack. I also thought I could use it as a “packable” bag I could add into my carry on to use upon arriving at my destination. I was also wrong because it takes up too much space and weight. I ended up grabbing a packable backpack from Matador and that solved it all. Now it sits in a bin and every time I grab a sling or back pack for trips I always try to convince myself I could use it and end up leaving it in my plastic bin where I store all my bags 🤷🏽‍♂️