Toyota · Honda · Hyundai · Kia · and 300+ more
Traffic doesn't get better. Your car can.
Tesla owners have had smooth highway driving for years. Now your car can too. We install a small device on your windshield and your daily commute changes completely.
The comma four.
A small device that mounts behind your rearview mirror. It connects to your car through the OBD-II port, uses three cameras to see the road, and runs openpilot to handle adaptive cruise and lane centering better than your car's stock system.
It works with 300+ car models. No modifications to your vehicle. Remove it anytime and your car goes back to exactly how it was.
What you actually get.
Not promises. These are the things the device does today, on supported cars.
Stop & Go in City Traffic
This is where it makes the biggest difference. In bumper-to-bumper city crawl, the device handles acceleration and braking for you. It follows the car ahead, stops when they stop, and moves when they move. You don't touch the pedals. It works in the kind of slow, grinding traffic where driving is most exhausting.
Follows Traffic Like You Would
Your car's stock system tends to leave big gaps in traffic and brake harder than it needs to. The comma four follows more naturally, keeping a closer, more consistent distance without the jerky stop-start you're used to. Other drivers don't cut in front of you constantly.
Highway Lane Centering
Predictive, not reactive. The system models the curve ahead and positions your car proactively, rather than correcting after you've drifted. Long highway stretches become noticeably less tiring.
Gets Better Over Time
The driving model is updated regularly. Each software update improves how the system handles curves, traffic, and different road conditions. The device you have today drives better next month than it does now. Updates happen automatically over Wi-Fi and LTE.
Access to Your Driving Footage
The device stores up to 10 hours of driving footage locally across its three cameras. Review your trips, check driving habits, or keep a dashcam record of your commute. Need more storage? Ask us about extended cloud storage options.
No Vehicle Modifications
The device mounts to your windshield and plugs into your car's OBD-II port. Nothing is cut, spliced, or permanently changed. Remove it and your car is exactly as it was before.
$99/month
We handle the device, installation, maintenance, and software. You just drive. Cancel anytime. We'll remove the device at no charge.
Start with a free trial. No payment required to sign up.
No credit card required. We'll reach out to schedule your install.
How it works
A small device on your windshield. No modifications to your car. We handle everything.
Sign up
Tell us about your car. We'll confirm it's compatible and schedule a time for installation.
We install it
We mount the comma four on your windshield behind the rearview mirror and connect it to your car's OBD-II port. Takes about 5 minutes. No tools, no drilling, no permanent changes.
Drive normally
Engage cruise control like you always do. The comma four takes over adaptive cruise and lane centering, handling stop-and-go traffic and highway driving. Your hands stay on the wheel and you stay in control.
Supported brands
The comma four works with 300+ car models from Toyota, Honda, Hyundai, Kia, Lexus, Acura, Genesis, Subaru, Ford, GM, Mazda, and more. Compatibility depends on your car having factory-installed adaptive cruise control and lane keeping assist.
Check full vehicle list →What is openpilot?
openpilot is open-source driver assistance software made by comma.ai. It runs on the comma four and uses cameras and your car's sensors to provide smoother adaptive cruise, lane centering, and traffic handling. It's the most widely used aftermarket driver assistance system available.
You're still driving.
This is driver assistance, not self-driving. Here's what that means.
Eyes on the road. Always.
The comma four uses a driver-facing camera to monitor your attention, not just steering wheel torque like most stock systems. It watches that your eyes are on the road and you're alert. If you look away for too long, it warns you. If you don't respond, it disengages. You are the driver at all times.
This is what the industry calls Level 2 assistance. That means the system handles steering, acceleration, and braking, but a human is always responsible and always in the loop. It's the same classification as Tesla Autopilot and every other production driver assistance system on the road today. The difference is in how well it does it. You're still driving, but the tedious parts of driving get taken off your plate. Rush hour traffic, long highway stretches, stop-and-go crawls. That's where the value is. You stay alert, the system does the repetitive work, and you arrive less tired.
Your responsibility
You are fully responsible for your vehicle at all times. The system can disengage without warning and you must always be ready to take immediate control. You must be capable of driving the car yourself in any situation. You must follow all traffic laws. Neither Spectacle nor comma.ai are liable for how you use the device on the road. This is an assistance tool. It helps you drive. It does not drive for you.
Learn more from comma.ai
For detailed technical information about how the comma four and openpilot work, including safety documentation, supported vehicles, and the open-source codebase, visit comma.ai directly.
Questions?
Tell us about your car and we'll reach out.