The 0431164281 is a round ferrite core assembly for 6.3mm cable. The common-mode conducted EMI from 1MHz to 300MHz frequency range. The polypropylene cases are meeting the RoHS restrictions of hazardous substances and have a flammability rating of UL94 V-0. Round cable snap-it assemblies are controlled for impedances only. Minimum impedance values are specified for the + marked frequencies. The minimum impedance is typically the listed impedance less 20%.