reversing kits

No matter how good at parking you are, there's no denying a reversing aid is a useful addition to any car. That's why it's becoming one of the most coveted bit of kit on new models. But what if you run something a little more modest, and want to retro-fit one?

We looked at eight aftermarket reversing aids to see which gets our backing. All the systems had one, two, three or four sensors, which were mounted in or on the bumper. When reverse gear is selected, they emit and collect signals which detect nearby objects.

The system's ECU translates the signals into a display or pattern of beeps which become more rapid as an object nears. Most aids also gave a beep as reverse was engaged to confirm the set-up was operating. But remember, these devices can never replace a driver's common sense and vigilance.

DIYers will find routing the wiring the most time-consuming job, but stick-on sensors are easy to place. However, the in-bumper type are far more tricky, especially on four- detector units. We'd advise professional installation, unless you're very competent. The position of a towbar is also worth considering - you should mention this when buying. Weigh cost against your skill, as professional fitting is about £100 if it's not included in the price.

Each kit was set up acc-ording to the instructions, taking note of sensor height and angle recommendations - all were put around 500mm from the ground. We took time to adjust sensitivity where appropriate and then backed up to a series of objects - another car, a large gas cylinder, a bike on its side and a 510x 80mm steel driveway post. We looked for how accurately each obstacle was detected as well as quality, and logical installation and clear instructions.

This four-stage detection device had what was by far the largest ECU (140x11x35mm), which wasn't the end of the world, although the size might cause installation hassles in some smaller cars. Its sensors feature Laver's ultrasonic flat beam technology and warnings came through a small, microphone-sized speaker. The Ultra Park impressed with its results on the car, gas cylinder and guard post tests, being nearly inch-perfect on all three. It detected the bike beeping at the beginning of the test, but struggled after that. Good kit and results, but not so hot on price, especially as it's a DIY installation.

This was a development of the last test winner, but with in-bumper sensors rather than stick-on ones. The unit was tested with the three detectors provided, but it would work with two if a tow bar was in the way. We liked the small display panel which showed distance to the object, which sensor was being used and housed the beeper. Although the car, cylinder and post results were good, it struggled to trace the bike at 50cm. It performed similarly to the Ultra Park (left), but its price helped it become our Recomm-ended choice.