Both an outer and an inner frame assembly consists of high grade aluminum which is bonded with a special welding process. For sizes 12” x 12” (305 mm x 305 mm) and up the access panels are equipped with a safety-system ( used in ceilings) to prevent accidental opening. This safety system must be reattached if the hatch is removed.
The reveal of 1/16 of an inch (1.59 mm) is visible between the outer frame and door hatch. The concealed snap locks open the access panel when pressure is applied to the spring loaded latch side ( no tools needed to open)
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