Cover & Liner: 14-gauge galvanized steel cover with a 22-gauge steel liner
Curb: 14-gauge galvanized steel, Optional: Double wall curb (curb liner at exterior)
Hinge: Tamper-proof hinge contained within hatch as part of a spring assembly
Latch: Turn handle
Spring: Greased compression springs enclosed in telescopic tubes, which counterbalance the door to require no more than 10 pounds of opening force
Hardware: Zinc coated steel, Optional: Stainless steel
Insulation: 1" thick rigid fiberglass in cover and 1" at curb perimeterMounting Flange: 3½"
Finish: Factory applied powder finish