The air filter assembly for the Ingersoll Rand SS5 air compressor will filter the air before it enters into the compressor for compression. 54406640 will include the internal filter element 32170979. The NPT threads are 3/4" male and will thread directly into the side of the pump.
This inlet air filter assembly is used on the following Ingersoll Rand air compressors
Part #: 24655656
Part #: 38460655
Part #: 38436721
Part #: PSL20
Part #: 32170979
Part #: 20100277
Part #: 97333546
Part #: 54571617