This Metra 40-GM21 adapter lets you connect an aftermarket antenna to your compatible 1998-2008 GM vehicle's factory-installed radio. Copper, polypropylene and steel materials and copper shielding provide durability. | Metra | | Antenna Adapter for Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac | Black | Best Buy