Digital Antenna 18" Antenna Extension - White. All extenders mount standard 1"14 threaded mounts. Use a center brace when the combined length of your antenna and all extensions is more than 8' Specifications for Digital Antenna 18" Antenna Extension: Manufacturer: Digital Antenna Color: White Fabric/Material: Fiberglass Features of Digital Antenna 18" Antenna Extension Heavy duty fiberglass Stainless steel ferrules 1"14 threaded top and base High gloss urethane finish Package Contents: Digital Antenna 18" Antenna Extension Digital Antenna 518-EW: 18" Antenna Extension - White