The City Adventurer Belt Bag is around 2.5 liters and can fit a lot more than you think. I use this as my go-to everyday bag, whether it's for running errands or my travel essentials. It's big enough to store travel documents like additional visas or passports, along with in-flight gear like headphones, chargers, power banks, and protective face masks. I like to carry a portable power bank, my wallet, keys, hand cream, hand sanitizer, the Tower 28 LipSoftie lip balm, an extra contacts case, the Naked Sundays SPF50 Lip Oil , a perfume oil, and a mini chocolate bar — all of which fit inside the belt bag.