No one is forcing you to buy it. Make a better one yourself then.
I'm not sure if the one's I bought were advertised as self cooling, they looked exactly the same and I've no idea how they would achieve this. They appear to have some gel impregnated foam inside that remains cold for longer after being placed in a cold environment. We also looked into raised beds, which seem like a good idea, but our chap was pretty elderly and we felt he might become a bit unstable getting off it when sleepy.
That's right, it's a cooling mat.
A warm area to lie down will be the last thing on a pets mind during a a heatwave .
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