Manhole Cover and Frame Galvanised Steel Recessed Block Pavior 600 x 450 is ideal for using in areas of block paving where it is desirable to have continuity of surface finish and pattern. They are recessed by 80mm to use with 60mm thick block paviors. The galvanised steel frame and cover accepts bedding mortar more reliably and better than plastic counterparts allowing for a more stable and durable finished product. It is suitable for light to medium loads up to 10 tonnes.