The SIRIUS FEA25D FM Antenna Satellite Extender Vehicle Kit is designed specifically for the Sportster 4 radio, providing users with enhanced signal reception while on the go. This unit, made by Sirius, includes one antenna extender and is ideal for portable satellite radios, offering convenience and improved audio quality for outdoor adventures or travel. The compact and durable design makes it easy to install and use, ensuring a seamless experience for Sirius radio enthusiasts. Please verify that the part number and pictures match the part you are replacing before ordering.