The 0444177081 is a round Ferrite Core Assembly for 25.15mm cable. The common-mode conducted EMI from 25 to 300MHz frequency range. The polypropylene cases are meeting the RoHS restrictions of hazardous substances and have a flammability rating of UL94V-0. Round cable snap-it assembly is controlled for impedances only. Minimum impedance values are specified for the + marked frequencies. The minimum impedance is typically the listed impedance less 20%.
Many of the snap-it parts have flat core equivalents
Single turn impedance tests for the 44 material performed on the 4193A vector impedance analyser