Application/Usage Grades: Class A - Light Duty / Suitable for Pedestrian Traffic ONLY Class B - Medium Duty / Suitable for Pedestrian, Car and Light Truck Traffic Class C - Heavy Duty / Pedestrian, Car and Heavy Truck Traffic These products are recommended for external use. This product includes Galvanised and Stainless Steel Grates. Proudly Australian Designed and made to Australian Standards To be safe, we always recommend going for the heavier duty if you are unsure between 2 options. Galvanised These full hot-dip galvanised grate and frames are available in various different patterns, suitable for various different applications. Heelguard Suitable in various different applications where a grate with smaller holes is required. The popular wedgewire pattern prevents leaves and foreign items from being collected into the drain. These are hinged and lockable. Grates are in 2 pieces on larger sized grates so it is easier to lift