I have a coleman xtreme 28l that i got for a 24hr ultra i used to do once a year where you setup a tent for your "home base" at the start/finish line between laps. I'd camp friday afternoon to sunday midday and if i put my perishable food in it with a couple of bags worth of "party" ice from the shop (no freezer) on the friday morning before I left there was still a surprising amount of ice in it on the sunday, enough for me to still have a cold drink after I packed up.
I bought a super cheapo cool box from Tesco for £12 on Thursday because everywhere was sold out of other options and Jana used it camping for two days and there was still ice in the bottom at the end of the trip. Flimsy and thin lid...assumed I had wasted my money. Turns out it worked well.
I have a coleman xtreme 28l that i got for a 24hr ultra i used to do once a year where you setup a tent for your "home base" at the start/finish line between laps. I'd camp friday afternoon to sunday midday and if i put my perishable food in it with a couple of bags worth of "party" ice from the shop (no freezer) on the friday morning before I left there was still a surprising amount of ice in it on the sunday, enough for me to still have a cold drink after I packed up.