Editorial disclosure: this guide was prepared for SuperReps by an administration-managed editorial profile. It is not a personal purchase or a first-hand product review.
External bag dimensions do not tell you whether your everyday items will pass through the opening. A clear capacity test is more useful than “it holds loads”.
List real objects
Choose a repeatable kit: phone with case, wallet, keys, glasses case and the specific extra item that matters to you. Give their approximate dimensions rather than posting sensitive contents. A paper rectangle can stand in for a device; label it as a mock-up.
Test the opening and closure
Show each item beside the empty bag, then the packed interior. Note whether the opening is narrower than the body, whether a divider reduces space, and whether the closure shuts without pressure. Do not force a zip or stretch the sides to claim a fit.
Show the loaded shape
Photograph the bag upright and carried, with private details hidden. State whether items can be removed without emptying everything else. Include strap setting and whether the bag tips when set down.
A useful answer reads: this exact kit fits, the closure works freely, but the glasses case blocks access to the wallet. That is more transferable than an unsupported capacity in litres. It also avoids treating a nominal size name as a guarantee of internal room.