1. **Plastic**: Most exercise wheels are made from durable, non-toxic plastic. Ensure that the plastic is thick enough to prevent cracking and is free from harmful chemicals.
2. **Wood**: Some wheels are made from untreated wood. However, make sure the wood is free from splinters and has not been treated with any chemicals or paints that could be harmful to your hedgehog.
3. **Metal**: Metal wheels can be safe if they have a powder-coated finish that is non-toxic. Avoid wheels with sharp edges or that can rust easily.
4. **Fabric**: Some exercise wheels have fabric surfaces to provide grip. Ensure that the fabric is non-toxic and can be easily cleaned or replaced.
When choosing a wheel, also consider the design. A solid surface is preferred over a wire mesh to prevent injuries to their feet. Additionally, the wheel should be large enough for your hedgehog to run comfortably without arching their back. A diameter of at least 12 inches is recommended for adult hedgehogs. Always supervise your hedgehog during exercise to ensure their safety.
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