Pros: Very quiet, moves a lot of air
Cons: Inlet restriction hampers it's airflow
Using the included ULNA makes this unit utterly silent, although performance will suffer quite a bit. The standard low noise adaptor should be all you need to make your system as quiet as possible without sacrificing too much airflow, but you do have the option to take it a step further if you really wanted to.
Overall an excellent product which is suited for internal airflow / case exhaust. Due to S12A's extremely narrow blades, you're better off using it where the fan's intake has little to no restriction.
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