Noctua 30cm 4Pin PWM Power Extension Cables The NA-SEC1 chromax.black is a fan accessory set consisting of four NA-EC1 30cm extension cables. The NA-EC1’s 4-pin connectors are compatible with both 3-pin and 4-pin PWM fans and the cables can be daisy-chained in case more than a 30cm reach is required when installing fans in larger enclosures. Thanks to the black sleeving, the cables are ideal for creating PC builds with neat, focused aesthetics and are a perfect match for Noctua’s chromax edition fans.