Cover: 1/4-inch (6.4mm) aluminum diamond plate cover reinforced for occasional, off-street AASHTO H20-44 wheel loading. Equipped with cast aluminum flush lifting handle and 316 stainless steel hold-open arm with red vinyl grip that automatically keeps the cover in its open/upright position. (Upon request, manufacturer shall provide structural calculations showing that the door desigh meets the loading requirements of AASHTO H20-44.) 
Lift Assist: Open stainless steel horizontal springs for easy opening
Frame: Extruded aluminum trough section with integral anchor flange on all four sides. Frame has an EPDM odor reduction gasket and 1 1/2-inch (38mm) threaded drain coupling. Bituminous coating on frame surface in contact with concrete.
Hardware: 316 stainless steel hinges and tamper resistant bolts/lock nuts.
Security: A 316 stainless steel slamlock with thread plug, removable outside key and fixed inside handle. The slamlock latches onto a 316 stainless steel striker plate that is bolted to the frame.   
Finish: Aluminum cover and frame have mill finish which is protected during shipping and installation by an attached adhesive-backed vinyl material.
Installation: Installation shall be in accordance with the manufacturer’s instructions. The entire frame, including the seat on which the reinforcing rests, shall be supported by concrete or other material designed to support the specified loading.
Warranty: Manufacturer shall guarantee against defects in materials and workmanship for a period of ten years.