Wow, I don't recall seeing anything like that in mine when I repaired/replaced my failing siren(s) batteries. BUT, that given, does it have a MB number on it? I noticed the plugs on the rear have MB numbers but I think that is just the plug MB part numbers. I also could not quite make them out to research them to backtrack. Could you please look for a molded MB part number anywhere on the part? An old toothbrush lightly scrubbing off the part might reveal it. That should reveal exactly what that part is (and for). Thanks (Quite a strange part I say).

Could it be a terminal block for the two W/W heating system (W/W jets are heated)? I wonder instead of running them through a grommet, they just created a terminal block for easy access/replacement. Total guess though.


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