This Clark-Drain manhole cover and frame is designed for 450mm inspection chambers and features a square, recessed locking mechanism. The galvanised steel tray has an internal depth of 80mm, suitable for block paving, concrete, or slabs, and complies with BS EN 1449:1991 and BS EN 1461:2009 standards. The frame is constructed from durable AP9 grade polypropylene. The size refers to the clear opening of 450mm, with the overall dimensions of the cover and frame being 580mm x 580mm x 88mm. The cover can be rotated to align with paving patterns, eliminating the need to cut paving around a circular opening. With a 10 Tonne load rating, it is appropriate for domestic driveways and pedestrian areas. The cover includes integral lifting keys for easy handling, tested to withstand a 120kg direct lift.