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About This Item

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.
  • Key Specs
    • Connector Type (End 1): Proprietary
    • Connector Type (End 2): Proprietary
  • General
    • Brand: Metra
    • Model Number: 40-GM21
    • Product Name: Antenna Adapter for Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac
    • Color: Black
    • Quantity: 1
    • Compatibility: Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac
  • Connectivity
    • Cable Type: Antenna
    • Product Type: Adapter
    • Connector Type (End 1): Proprietary
    • Connector Type (End 2): Proprietary
  • Warranty
    • Warranty - Parts: 1 year
    • Warranty - Labor: 1 year
  • Other
    • UPC: 086429007073

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.

  • Compatible with most 1998-2008 GM vehicles: For use with your existing model.
  • Antenna adapter: Enables you to connect an aftermarket antenna to a GM factory-installed radio with a mini barbless connector.
  • Copper, polypropylene and steel materials: Offer a durable design.
  • Copper shielding: Promotes optimal performance.
Whats Included
  • Metra Antenna Adapter for Most 1998-2008 GM Vehicles

Q: What is this product made of?

A: This adapter is made of copper, polypropylene, and steel materials for durability.

Q: How does the copper shielding help this product?

A: The copper shielding promotes optimal performance.

Q: How many adapters are included in the package?

A: This product comes with one adapter.

Q: Does this antenna adapter work with other car brands?

A: Yes, it is compatible with select 1985-2013 Chevrolet, GMC, Hyundai, Kia, Buick, Cadillac, and Pontiac vehicles.

Q: What does this antenna adapter do?

A: This Metra adapter allows you to connect an aftermarket antenna to your compatible 1998-2008 GM vehicle's factory-installed radio.

Q: Will this fit a 2008 avalanche. I just recently went to the local store and the one they gave me says it’s for Chrysler’s

A: Take your car to the Geek Squad at best buy the tell you the exact one that will fit your car, that's what they did for me.

Metra - Antenna Adapter for Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac - Black

Model: 40-GM21
SKU: 6423596
$14.99
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Reviews

Customers are saying

Customers appreciate the easy installation of the Antenna Adapter. It is noted to be particularly useful when using XM Onyx radio in certain GM vehicles.

This summary was generated by AI based on customer reviews.

The vast majority of our reviews come from verified purchases. Reviews from customers may include My Best Buy members, employees, and Tech Insider Network members (as tagged). Select reviewers may receive discounted products, promotional considerations or entries into drawings for honest, helpful reviews.

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Pros for Metra - Antenna Adapter for Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac - Black
Compatibility, Fit, Installation, Antenna Adapter, PriceInstallation, Compatibility, Fit, Reception, Ease of useThere were no pros for this productThere were no pros for this product
Cons for Metra - Antenna Adapter for Select 1985-2013 Chevrolet GMC Hyundai Kia Buick Cadillac Pontiac - Black
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