Flask (Hillsborough S6)

Before I get rid of it would anyone like this flask? It's great at keeping hot things hot and cold things cold but if you turn it upside down the closure mechanism leaks a bit. This is fine if you aren't going to turn it upside down but we've had one too many walks where it has leaked into the bottom of a rucksack! It may be that it takes a standard lid, or the mechanism can be fixed but we have another one we use instead so haven't looked into it.