The dogs most at risk in hot weather are the ones who refuse to stop. A retriever will chase a ball into heatstroke because the drive to fetch overrides every signal the body is sending, and the owner is usually the only brake in the system. This ball works with that instead of against it: fill the silicone inner shell with water, freeze it overnight, and the thing the dog wants to carry becomes the thing that cools its mouth.

As the ice melts from the inside out, water is released slowly through play rather than all at once, so the dog takes on a little moisture every time it brings the ball back. The orange and blue colourway is chosen for visibility, which matters more than it sounds when a ball lands in long dry grass or floats among reflections on water. The medium measures 6.5cm across.

• Freezable internal reservoir that releases water slowly during play
• Easy-fill silicone freezer shell
• Helps cool and hydrate dogs in warm weather
• High-visibility orange and blue, on land or in water
• Medium size, 6.5cm diameter
• Priced at GBP 8.45

On size and supervision. At 6.5cm this is a medium, and for a large-mouthed dog such as a big Labrador or a Mastiff a ball this size is a choking risk rather than a toy. Check it against your dog's mouth. It is a fetch ball, not a chew toy, and determined chewers should not be left alone with it.

Who it's for: Owners of energetic fetch-driven dogs of medium build who play through the summer and need something that cools as well as entertains.