Special Clearance - 450 x 450mm Opening Solid Top Cover - 50mm HeightClarence Whilst Stocks Last Solid top access cover for internal use or sealed external applications. Stops odour and lowers possibility of storm water surges. Measurements Clear Opening 450mm x 450mmExternal Dimensions 550mm x 550mm x 50mm* *Not including any strengthening supports measuring 50mm Tech Spec Galvanised steel tray and frame Four securing screws Two lifting keyhole cups CD 552 Lifting Keys can be used to lift the tray and gain access to