Properly waterproof, but absolutely not for all day, every day, long distance walking. These were used on the Skye Trail when feet got VERY wet and there was nothing for it but to wear these for some respite (wet feet get soft and blister far more easily).
Feel mildly peculiar to wear, breathability isn’t a great strength, nor really is comfort. Better for more static use like grouse shooting or watching sport in the open air in muddy fields