Milcor hatch covers open easily to 90 degrees. Operation is assisted by enclosed torsion bar or torsion coil spring operators. Automatic hold-open arms keep doors securely open.

Heavy, closed cell, rubber gaskets factory-applied to the units provide a barrier to weather penetration and drafts. Latching devices with inside and outside handles hold hatches tightly closed.

Milcor heat and smoke vents can save lives by releasing smoke, decreasing the possibility of deadly smoke inhalation to building occupants. The open covers permit firefighters to douse flames directly from the rooftop location.