Metra CFRM4 is a 4 inch black billet antenna mast with a carbon fiber inlay. Compact design is perfect for roof mount applications but can be mounted on fender as well. Metra antenna works aftermarket antennas are designed and engineered as a complete system that functions seamlessly in every application and every weather condition. Please note on fender applications reception may be lost if the OEM antenna is 30 inches or above. Multiple threaded adapters included to fit most vehicle antenna bases.