It's a "Fire" NEMA. It's red to tell people there's a fire box (those red things that were used before cell phones that were pulled down to call the fire department) these are obselete now though.
What i find odd is that these run 24/7. As you can see, the NEMA head has a shorting cap in it so it's on even during the day instead of just at night. It's not like these give off much light anyways lol. I wouldn't mind coming accross one of these some day though. They're pretty cool in my opinion.
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I've seen those fire boxe in Boston when I've traveled there last summer, cool to know! 