The next time you invite your mother in law over for a meal, why not turn uncomfortable silences into ominous ones with these not-quite-cute accessories? As you can see, they’re uncompromisingly intimidating: each is as large as, well, a human head.

While they won’t fool a doctor, they probably aren’t a good idea for children’s parties. They look real enough to at least provoke a double-take and probably aren’t a good idea at children’s parties.

Bear in mind that these come in numerous colors and shapes; have a look around to find your favorite (if that’s the right word here).

On some, the lower jaw bone is loose so the mouth can be left open as if screaming, others have hollow eye sockets to let the flames through, and one option has very unsubtle horns in case normal skulls aren’t creepy enough already.

Each is reassuringly heavy at about ten pounds and is reinforced with steel wires inside. They will probably break if you drop them, but are made of a special ceramic material that won’t be harmed by any temperature short of what you’ll find in an industrial furnace.

Best for Gas

Note that these are basically just shaped lava rocks like you’d find in most gas fire pits and hearths.

If you want to use them in an ordinary grill and perhaps barbecue over them, you’ll have to use a gas grill or opt for skull-shaped charcoal briquettes instead.