Swiftech MCX462-V HSF
 

The Helicoid pin design increases surface area of the pins. This
increased surface area creates a more effective mechanism for heat
dissipation. Also these pins are aligned in concentric rows which are
bent at different angles. Swiftech says “The spacing and angles between
the concentric rows has been precisely calculated to optimize cooling
and reduce noise at air flow levels as low as 22 CFM and 23 dbA.

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