WOLFBOX G840S 12″ 4K Mirror Dash Cam: Honest Review
The WOLFBOX G840S 12″ 4K Mirror Dash Cam Backup Camera with 32GB Card and GPS | 5.8GHz WiFi Smart Rearview Mirror for Cars & Trucks, Front and Rear View Dual Cameras, Night Vision, Parking Assistance is aimed at drivers who want a dash cam and a large digital rear-view screen in one unit.
I have not personally road-tested this exact unit, so I will not pretend I have. This review is based on the current Amazon listing, WOLFBOX product information, the manual, and real owner feedback. On paper, the G840S looks strongest for daily drivers who want a wide mirror display, front-and-rear recording, GPS, and simple app access without paying flagship money.
| Overall: 4.4/5 | Performance: 4.3/5 |
| Value: 4.6/5 | Design: 4.5/5 |
| ✅ Best For: Drivers who want a big mirror screen with front and rear recording | |
| ❌ Not Ideal For: Buyers who need top-tier rear-camera detail or built-in parking power | |
| Price: Around $129.98 on Amazon when checked; prices can change | |
| Check Price on Amazon | |
What Comes in the Box?
The package is fairly complete for a dual-camera setup. The listing includes the 12-inch mirror unit, rear camera, external GPS module, power cable, rear-camera cable, rubber mounting straps, adhesive pieces, trim tool, and a 32GB memory card.
The main mirror straps over the factory mirror instead of sticking to the windshield. That is useful if you dislike suction mounts. The harder part is the rear camera. You still need to route its cable through the cabin, and the supplied rear lead is about 20 feet long.
How the G840S Performs
The G840S combines a 4K 2160p front camera with a 1080p rear camera. That split makes sense for evidence capture because the front view normally needs the most detail. The rear feed is more about coverage, reversing help, and documenting what happened behind you.
Daytime Highway Driving
In bright daylight, the listed 4K front resolution gives the G840S enough detail for road signs, lane markings, and nearby vehicles. The front lens is listed at 170 degrees, so it covers a wide scene. A wide lens can make far-away plates look smaller, though, so do not expect every distant plate to read like a close-up.
Busy City Traffic
The 12-inch screen is one of the main reasons to buy this model. You can switch between front, rear, and split views. The rear camera is listed at 140 degrees, which helps with traffic beside and behind the car. The large display can also be easier to glance at than a small two-inch dash cam screen.
Night Driving
WOLFBOX lists WDR, HDR, a low-reflectivity display, and a six-glass lens. Those features are meant to control bright headlights and dark areas. Night footage will still depend on street lighting, speed, rain, and plate reflection. The front camera should remain more useful than the 1080p rear unit when detail gets difficult.
Rain and Mixed Light
Rain, glare, sunset, and wet roads are tougher than clear daylight. The G840S has tools to balance exposure, but no dash cam can fully remove motion blur or blown highlights. The useful point is that the mirror screen lets you adjust the displayed view while the cameras keep recording.
Parking and Impact Events
The G-sensor can lock important clips after an impact, while loop recording keeps old normal files from filling the card forever. Parking monitoring is supported, but a separate hardwire kit is required. Without that constant power source, the camera cannot provide true 24-hour parking coverage after the car is switched off.
Living With It Every Day
Daily use should be simple once the cables are hidden. The unit starts with the car, records to the microSD card, and can show front, rear, or dual views. Wi-Fi lets you connect through the WOLFBOX app to view recordings and share clips without pulling the card every time.
The small daily annoyances are predictable. A 12-inch glossy screen can show fingerprints. Bright sun can create reflections. The rear cable takes patience to hide, especially in a hatchback or truck. GPS adds another cable and module near the windshield. None of those issues are unusual, but they matter more than the spec sheet suggests.
Mirror Design and Build
The G840S is designed to sit over the stock rear-view mirror with rubber straps. That keeps the windshield cleaner than a second screen stuck to the glass. The curved 12-inch display gives it a more factory-like look than many add-on cameras.
| Part | What to Expect |
| Display | 12-inch touchscreen mirror |
| Mount | Rubber straps over factory mirror |
| Rear camera | 1080p wired camera |
| GPS | External module included |
| Storage | 32GB card included |
The setup is compact at the front, but cable management decides whether it looks clean. The rear camera and GPS wiring should be secured so they cannot tug on the mirror or rattle against trim.
Video Quality After Dark
Daylight is where the G840S should look its best. The front camera has far more pixels than the rear, so front footage has the better chance of holding road detail. At night, WDR and HDR can help keep bright lamps from washing out the whole frame.
The rear feed is still useful for context, reversing, and close traffic, but 1080p gives it less room for cropping. In heavy rain or dark roads, I would treat plate capture as a bonus rather than a guarantee.
Cleaning and Maintenance
Maintenance is easy, but it should not be ignored. A dirty front lens or rear camera can ruin the very clip you bought the system to capture. Wipe both lenses with a clean microfiber cloth and keep the mirror screen free of greasy smears.
| Task | Simple Routine |
| Lens cleaning | Check every few weeks |
| Memory card | Review and format as needed |
| Cables | Check for pinching or wear |
| Mount straps | Check tension occasionally |
Also test saved clips now and then. Loop recording only helps if the card is healthy. If the camera starts missing files or showing storage errors, replace the microSD card before you need evidence from it.
WOLFBOX G840S Pros and Cons
The G840S offers a lot for its price, but the lower-resolution rear camera and hardwire requirement are real compromises.
Pros
| Cons
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How It Compares
Two useful alternatives are the WOLFBOX G900Pro and Pelsee P12 Pro. Both add features the G840S lacks, but they target buyers with different priorities.
G840S vs G900Pro vs P12 Pro
The G900Pro is the premium step up. It uses newer imaging hardware, supports higher rear-camera detail, Wi-Fi app control, voice control, and up to 512GB storage. The Pelsee P12 Pro keeps a 12-inch mirror layout but adds ADAS, blind-spot alerts, and voice control.
| Model | Main Advantage | Best Fit |
| WOLFBOX G840S | Value + big mirror | Most daily drivers |
| WOLFBOX G900Pro | Better camera hardware | Premium footage buyers |
| Pelsee P12 Pro | ADAS + voice control | Feature-focused drivers |
If budget matters, the G840S makes the stronger value case. If rear footage quality matters as much as front footage, the G900Pro is the more serious upgrade. If driver alerts and voice commands matter most, the Pelsee is worth comparing.
Who Should Buy the G840S?
Buy this if:
- You want a large digital rear-view display.
- You want 4K front recording plus rear coverage.
- You value GPS and Wi-Fi without a premium price.
- You prefer a mirror-mounted system over a windshield screen.
Avoid this if:
- You want matching high resolution front and rear.
- You need parking mode without hardwiring.
- You do not want to route a rear-camera cable.
Long-Term Durability
The main long-term wear points are the rubber straps, cable connectors, rear-camera wiring, touchscreen surface, and memory card. Heat cycling inside a parked car can age all of them. Keeping cables loose enough to avoid strain and using a reliable card should help.
WOLFBOX lists a 12-month guarantee on the Amazon page. I would also keep the receipt and check the saved footage every month or two. A dash cam can appear to be working even when a card has started failing.
Power and Installation
Normal driving use is simple: power the unit from the car and route the front and rear cables cleanly. The mirror itself straps on without drilling. The rear camera needs a longer wire run, and the GPS module needs a suitable windshield position.
For parking monitoring, use the compatible hardwire kit. The listing does not provide a clear real-world watt draw for recording versus standby, so I would not invent one. A proper hardwire kit matters because it gives parking mode a controlled power source instead of leaving the camera on a basic socket.
WOLFBOX G840S FAQ
These are the practical questions most buyers should answer before ordering.
Does the WOLFBOX G840S record in 4K?
Yes. The current listing states 4K 2160p for the front camera and 1080p for the rear camera. The front channel is the one designed for the highest detail.
Does the G840S have Wi-Fi?
Yes. The current version lists 5.8GHz Wi-Fi and uses the WOLFBOX app for live viewing, playback, settings, and clip sharing.
Does parking mode work without hardwiring?
No, not for full 24-hour monitoring after the vehicle powers down. WOLFBOX states that a compatible hardwire kit is required for parking monitoring.
Is a memory card included?
Yes. The current Amazon listing includes a 32GB card. Larger compatible cards can give you more recording time before loop recording overwrites older normal clips.
Can the G840S replace a normal rear-view mirror?
It mounts over the factory mirror and can show the live rear camera feed. The screen can also switch off so the surface works more like a normal mirror.
| Verdict: A strong-value mirror dash cam for drivers who want a big rear view and solid front recording. |
| Price: Around $129.98 when checked; verify the live Amazon price. |
| Amazon rating: 4.3/5 from 14,727 ratings when checked. |
| Check Current Price & Availability |
Final Verdict on the G840S
The WOLFBOX G840S makes sense if your priority is a large mirror display, 4K front recording, rear coverage, GPS, and Wi-Fi at a mid-range price. It packs the features most daily drivers actually use, and the 32GB card means you can start recording without buying storage on day one.
The trade-offs are clear. Rear video is only 1080p, the wiring takes effort, and parking monitoring needs a separate hardwire kit. I would recommend it for drivers who care more about value and a wide digital rear view than having the newest sensor hardware. If you want stronger rear footage or premium low-light performance, step up to a newer model.
I’m Alex Rahman, a car enthusiast and automotive writer focused on practical solutions, car tools, and real-world driving advice. I share simple and honest content to help everyday drivers make better decisions.
