Our keyholes are made of PA reinforced nylon, which is of the highest quality, ensuring durability and longevity. The use of PA-reinforced nylon makes it extremely tough and able to withstand the wear and tear of daily use. Say goodbye to fragile keyholes that break easily because our products are built to last! One of the outstanding features of our keyhole is the perfect diameter it offers. The keyhole diameter is 9mm, which is perfect for various circuit breakers on the market. This ensures a seamless fit and eliminates any concerns about compatibility issues. We understand the importance of accuracy and compatibility, so we make it our top priority to provide keyholes to fit a wide range of circuit breaker models.