H4 Car HUD Head-Up Display - GPS Speedometer with Auto-Dimming, Real-Time Speed and Compass Direction, KM/H or MPH Switchable, Windshield Projection Display for All Vehicles.

This worked pretty well. I have a heads-up display on my car, so I wanted to get one for my daughter. Her speed control is not very good. She tends to drive too fast, then too slow -- not at a steady speed. I am hoping that the digital readout will make her more conscious of her speed. Since I started using a car with an integrated heads-up display, I've become much more conscious of my speed. It's easy to install. I would recommend getting a USB hub as it will use up one of the USB ports (nowadays, those are cheap and available). It only does speed measurement and it's as accurate as GPS can be, which is to say not as perfect as an integrated HUD. However, the device can be calibrated for accuracy (add or subtract a few mph, as needed). It also shows direction (North, East, South and West; when going in between, both lights are lit (e.g. both N and W when pointed northwest). The cord is unsightly, but if you saw my daughter's car, that would be the least unsightly thing you'd notice (think pizza boxes and water bottles). It was not obvious to me how to position it so that the display was perfectly straight up and down (if that matters to you) because her dashboard is curved. I found the best orientation and left it at that. It comes with a reflective rectangle, but making that match up to the display was not an obvious task and frankly the display is bright enough without it (although I have not observed it during night driving). This device is so cheap it's really a wonder why anyone would go without a heads-up display. Well, I think my fussy wife might object to the visible cord and even seeing the device on her dashboard. But for an after-market device, I find it perfectly suitable.

The gas gauge in my 67 Dodge Charger doesn't work, so I filled my tank according to how many miles since last fill-up. When the Speed and odometer died to, I needed a quick fix. This was it, and I LOVE it. It's compact, and I discovered it doesn't even need to be ON the dash to work right: I mounted below dash where a radio used to be, it's very discreet yet gives me clear indication of speed and milage, exactly what I needed.

It looks the part, but does not function as advertised. The instructions are unclear and the set-up is difficult. For me there is a 10 mph discrepancy in the mph.

Great visibility, great idea... doesn't work at all. 1) Never stops searching for satellites 2) never works. 3) the manual is readable but not the best. Is there a reset? What if it gets stuck searching for GPS satellites? update: replacement DEVICE WORKS PERFECTLY

I wanted a digital compass for our car (which has no built-in compass). This fits the bill and I do appreciate the large digit clock and speedometer which can also be displayed. I calibrated the speed to match my GPS speed and it works well. To get exactly the viewing position I wanted, I used a small strip of black duct tape to secure the power cord to our black dash and that has worked perfectly to hold the unit steady. There is an adhesive strip included with the product. The auto-dimming feature- still too bright at night, but I placed the unit at a dash position that is not so annoying. You have several selections for the display and I prefer time of day- often when the unit starts up it has changed to odometer or elapsed time and I have to reset to time of day. I've quickly learned how to make that switch. The time of day updates via GPS, but it does not automatically switch when crossing time zones, so you have to change that in one of the menu functions. For the price and features, I'm happy with the choice of this product.

Item returned not due to quality. Requires a reflective screen on the inside of the windshield and due to the limited area for my application it would be too obtrusive for me. Also could not reach adjustment buttons and it cannot be removed and then returned since the mounting is meant to stick permanently.

This item is great! I really enjoy it. The only thing missing is I wish it displayed the current speed limit. I will have to look and see if there is one that does that.

Unobtrusive, good image projection, clear colorful image on windshield, cable provided is long enough to reach rear power source. Excellent accuracy. Could have better use instructions.