How long do your bottles/cups stay cold?

Bottles & Travel cups – We claim “stay hot or cold for up to 24 hours (bottles)/12 hours (travel cups)”, but how cold is cold? The science bit: we measure that there is only a 20% increase in original temperature over a 24 hour and 12 hour period. So one could claim they stay “chill” for longer. Cold or chill, your Smidge bottle will still be as cool as a cucumber after a days outing.