For a replacement wheel tread for a robot vacuum, a silicone material with a lower shore hardness would be more suitable for increased traction. You may want to consider a silicone material with a shore hardness of around 10A to 30A for better grip and flexibility. However, the exact hardness may vary based on your specific requirements and the surface the robot vacuum will be operating on. Conducting small test prints with different shore hardness levels can help determine the optimal choice for your application.
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