The NA-IS1-12 Sx2 is a set of two 5mm thick intake side spacer frames for Noctua 120x25mm fans that can help to improve both acoustics and performance in suction or “pull” type applications where the fan draws air through obstacles such as grills, perforated plates, mesh panels, filters or radiators.

By offsetting the fan from the obstacle, the NA-IS1 inlet spacer reduces influx turbulences, which can, depending on the application and fan model, not only improve airflow but also significantly reduce overall noise levels and make the fan sound more pleasant to the ear. Designed to replace the fan’s stock NA-AVP1 anti-vibration pads, the NA-IS1-12 are compatible with all current square-frame Noctua 120x25mm fans and extremely straightforward to install: For case fan applications, either the supplied self-tapping screws or the included NA-AV3 anti-vibration mounts can be used to sandwich the spacer between the fan and the case panel.

For radiator mounting, both M3 and UNC 6-32 screws are supplied. In sum, the NA-IS1-12 Sx2 set is a simple yet highly effective fine-tuning measure for suction type applications where a reduction of influx turbulence can lead to improved airflow and acoustics.