Hexatronic NDK12103 (Millennium part 523409) is a 100-piece pack of 5 mm microduct strain reliefs used where microduct terminates into a closure, cabinet or transition fitting. The strain relief anchors the duct so pulling and thermal movement load the fitting rather than the fiber inside, preventing the slow attenuation creep that follows an unsupported duct entry. Bulk packaging suits production microduct work where a single cabinet may take dozens of terminations. Compatible with Hexatronic HDPE microduct systems and the couplers and sweeps used alongside them on FTTH builds.