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SMC makes various filters that would probably be the same, but they are usually grey. The bottom piece with the wire attached is a solenoid valve that opens to automatically empty the water collected in the bow when the compressor shuts down. They are also types that have a float valve to perform the same function.
This filter is to collect water condensed from the compressor. But they are somewhat notorious for leaking either from a cracked bowl or the o-ring mainly due to vibrations from being hard mounted to the compressor. You could re-plumb it with a piece of tubing from the compressor to the filter to help prevent this from happening.