This is my second bag from Bellroy. I bought this sling mainly for having a light bag for work and day trips while on vacation. It's also perfect for flights. It can fit my 500ml Hydroflask, a power bank and my Nintendo Switch 2 along with a few small accessories. I can also use it for my camera, but that requires sacrificing either the water bottle or the Switch 2. The description claims 9 litres space, but in reality it's around 5 litres (common issue with Bellroy slings). It's got a very compact form factor and doesn't get in your way. When lightly loaded, it's barely noticeable. Overall, I am quite pleased with the purchase.