Description SilverLine® Unarmored Test Cable, 4.0 Feet, Super Flex 18GHz, NM/NMR. SilverLine® Test Cables are cost effective, durable, high performance cable assemblies designed for use in a broad range of test and interconnect applications. Fabricated from rugged, solid PTFE dielectric cable with stainless steel connectors and a proven strain relief system, these cables provide long life and excellent stability in applications where they are repeatedly flexed and mated/unmated. RoHS Compliant.