|G SERIES 685mm ID/913mm OD|
Grade Rings are used to adjust the top elevation of the cast iron or steel frame and cover to the finished grade of the roadway.
|H SERIES 750mm ID/930mm OD (Bell & Spigot)|
|HR SERIES 685mm ID/1059mm OD|
|F SERIES 900mm ID/1200mm OD|
|SQGR Series 610mm ID/840mm OD|