Montblanc Sartorial Nano Messenger Black 198165.

Though impressively compact, this nano messenger bag crafted from saffiano leather packs a sartorial punch. Perfectly sized to hold a standard smartphone in the main compartment, there’s also a zipped pocket on the front for your small belongings. Wear it as a crossbody or over the shoulder with the detachable leather strap, or carry it as a pouch.