A fastening mechanism for coupling track rail to a substrate includes a fastener body formed by a metallic base and an overmolded non-metallic coating. Metallic pillars are coupled with the fastener body, and define bores for receiving anchors held fast within a substrate. The coating encases the metallic base and extends peripherally around the metallic pillars to position vibration-attenuating non-metallic material between the metallic base and the metallic pillars.