Cameras that send an image to a dashboard-mounted screen when you shift into reverse are increasingly common on new cars, but since they are often bundled with navigation systems, they can add $2,000 or more to the price. Less-expensive aftermarket systems can be tricky to install, since most require wires from the license plate to the dashboard.

Now there’s a promising alternative: The VR3 VRBCS300W, from Virtual Reality Video Labs, uses a wireless transmitter activated by the backup lights. It’s priced at $149, and we’ve seen it for less than $100.

We found the VR3 relatively easy to install and effective enough to be an alternative to factory systems. The screen is small enough not to block your view ahead and it is easy to use, with a brightness control that can help improve the picture. But it’s not perfect. The small size can be a drawback, making the screen hard to see; and the view is flatter with less coverage than the fish-eye commonly used in factory-installed systems provides. At night, the image can be hard to see unless your brake lights are on.

Still, it’s hard to go wrong for the price. Whether you’re looking for added safety when children are around or trying to make trailer hookup easier, this device could merit a look.

Note: Consumer Reports' engineers conducted a short, initial test for this report, and we are now conducting a longer test of this product.