"A sealed lid for the 315mm diameter chamber assembly for use on areas where light traffic only (35kN). Quick & easy to install. Lightweight. Durable."
"A sealed lid for the 315mm diameter chamber assembly for use on pedestrianised areas only. Quick & easy to install. Lightweight. Airtight - double sealed & can be used for internal areas. 35kN loading capability. Height & tilt adjustable frame."