What makes the Cobra RAD 390 different from the RAD 380?

The Cobra RAD 390 builds on the RAD 380 with improved detection performance, providing greater range and more reliable alerts. It also features a redesigned windshield mount for a more secure, easier installation, USB-C connectivity for modern charging and firmware updates, and Extreme Mode for maximum detection sensitivity when you need it most.

Does the RAD 390 connect to an app?

No. The RAD 390 does not feature Bluetooth® connectivity. However, you can still use the Drive Smarter® app as a standalone app on your smartphone to access features such as red light and speed camera alerts, community-reported road hazards, and shared threat reporting from other drivers. Because the RAD 390 does not connect to the app, alerts and settings are not shared directly between the detector and your phone.

Can the RAD 390 be updated?

Yes, the RAD 390 supports free firmware updates, allowing you to receive ongoing performance improvements and feature enhancements over time.  

What types of radar and laser signals does it detect?

The RAD 390 detects X, K, and Ka radar bands, as well as laser signals from both the front and rear using LaserEye® technology.  

Does it reduce false alerts?

Yes, the RAD 390 uses next-generation filtering to help identify real threats while minimizing alerts from automatic doors, traffic sensors, and other non-police sources.  

Is the RAD 390 legal to use?

Radar detector laws vary by state. The RAD 390 is legal for passenger vehicles in most U.S. states, but it is not permitted in Virginia, Washington D.C., or for commercial vehicles nationwide.  

Will this work with my car?

Yes, the RAD 390 is compatible with all standard passenger vehicles and installs easily via your vehicle’s 12V power outlet or USB Type C connection.  

How do I mount the RAD 390 in my vehicle?

The RAD 390 includes a redesigned adhesive windshield mount for a secure, low-profile installation. It’s easy to set up and stays firmly in place.  

Can I customize alerts and sensitivity?

Yes, the RAD 390 allows you to adjust sensitivity modes and filtering settings to match your driving environment and preferences.  

What is Extreme Mode?

Extreme Mode increases sensitivity for faster response times and improved detection range—ideal for highway driving where early alerts matter most.  

Does it require a subscription?

No subscription is required to use the radar detection features. The Drive Smarter® app is free to download and use.  

What comes in the box?

The RAD 390 includes the radar detector unit, adhesive windshield mount, power cord, and quick start guide.  

What kind of warranty does it have?

The RAD 390 includes a limited 1-year manufacturer warranty.   

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