That looks like a gas/vapor explosion proof combination starter/disconnect to me.
Please note that NEMA classifications are NOT "tiered." That is, one class is not automatically "better" than another. This is a good example of such a confusion.
A "Class I" enclosure (for gas/vapors) often relies upon venting; there is NOT a test for surface temperature, especially when covered with dust.
A "Class II" enclosure often is sealed with a gasket. It is also tested by burying in dust, then monitoring the temperature of the case.
It is very possible for a "Class I" device to fail a "Class II" test. Almost any "Class I" incandescent lamp will fail a "Class II" test.
