• System detecting obstacle using Ultrasonic Wave (Sonar) Echolocation Technology
• Wireless LED Digital Display (no wiring between the display and main control box) with Built-in Audible Alert (Beeper).
• Audible Alert (Beeper) On/Off Switch
• Wireless Range: 66 feet (20m)
• 7 LED Lights (3xGreen/2xYellow/2xRed) on each side of distance display indicating orientation of obstacles and Safe/Warning/Stop zone
• Beeping faster if closer to obstacle and continuously if within 1.0ft (0.3m) from the obstacle
• Designed for cars, suvs, 4x4s, vans, pickups, trucks, RVs, Trailers, and Buses.
• Sensor Detection Range: 1.0 - 4.9 feet (0.3m - 1.5m)
• Distance Display in feet or meters
• 4 rear sensors giving good coverage of the rear end of your vehicle when backing up
• In-bumper type sensors giving the look of factory installed system
• Each sensor with wedge-shaped plastic spacer for adjusting to non-vertical bumper surface
• Perfect for backing up, street parking, parallel parking, garage parking, and parking in tight spot ...
• Powered by tapping into the wires of back up light
• Activated when vehicle is put in reverse
• Brand new in original factory box
• Low prices
• Shipping from USA
• 12 month warranty

Having the system is like having eyes in the rear of your vehicle and can help you avoid costly accidents and injuries.  
 
The Parking Sensor System is designed for all types of vehicles. It is especially useful and helpful in SUVs, VANs, trucks, full size cars, RVs, Trailers, and Buses which have poor rear visibility.  
 
It is a perfect parking aid for backing up/reverse parking, street parking, parallel parking, garage parking, and wherever parking in tight spot ...  
 
It can detect still and moving objects including children and small pets in rear blind area of your vehicle. Four sensors embedded into the rear bumper detect objects up to 4.9 feet (1.5m) from the vehicle.  
 
Your small kids or pets will never again be in danger of getting in the way of your vehicle while you are backing up.  
 
You never again have to get someone to watch the rear of your vehicle while backing up.  
 
With this 4 sensor backup parking system, you won't have to worry about getting too close to the car in rear of your vehicle, or scraping them while getting out of a tight parking spot.

The CPU in the main module of the Parking Sensor System determines obstacle distance by measuring the time needed for the ultrasonic wave emitted by a sensor to reach an obstacle and for the sensor to receive the ultrasonic wave reflected from the obstacle. Given the speed of the ultrasonic wave, the CPU can then calculate the distance between the sensor and the obstacle. That is also the reason some people call Parking Sensor System as Parking Radar because of the similarity in determining obstacle distance.  
 
The system is powered by +12V from back up light. The four rear sensors are activated when vehicle is put in reverse.  
 
The system comes with a wireless digital display which shows the exact distance from an obstacle and eliminates the wiring between the display and main control box. The wireless display can be mounted up to 66 feet (20m) away from the main control box (it still requires its own +12V power supply). This is especially convenient for installation on long vehicles.  
 
Seven (7) LED Lights (3xGreen/2xYellow/2xRed) on each side of the wireless distance display indicate both orientation of obstacles and Safe/Warning/Stop zone.  
 
The audible alert (beeper) is built in the wireless display. It beeps faster as vehicle gets closer to obstacle and sounds continuously when vehicle is within 1ft (0.3m) from the obstacle.  
 
The display starts to show distance when an obstacle is under 4.9 feet (1.5 meters) in rear of the vehicle. The beeper starts to sound when an obstacle is under 4.9 feet (1.5 meters) in rear of the vehicle. The display will show distance as 0.0 when you get within 1 foot (0.3 meter) to avoid colliding because of the inertia of vehicle while parking.

Note [1]: Even if you apply the brake, depending on your driving speed, your vehicle will still go for some distance before it comes to a complete stop. To be safe while parking, keep your vehicle speed at about 3 miles per hour.  
 
Note [2]: The parking sensor system detects obstacle by emitting ultrasonic wave and receiving reflected ultrasonic wave from an obstacle. Different materials have different reflection and absorption of the ultrasonic wave, and the actual detection distance varies depending on what materials an obstacle is composed of.  
 
For example, human skin and clothes actually absorb the ultrasonic wave, and can only reflect very small portion of the ultrasonic wave back to the sensors, hence the system may detect human skin and clothes in a much shorter distance compared to other materials.  
 
Also, the system may fail to give both visual and audible alert if an obstacle has smooth ball-shaped or sloped surfaces as such surfaces may not reflect ultrasonic wave back to the sensors at all.  
 
Drivers in these situations should pay more attention while parking their vehicles.

 
 
Dimensions of the Main Control Box

For detailed wiring and installation instructions, please view or download the User's Manual in PDF format. You need the Adobe PDF file reader to view it.

Inside the Retail Box

The Retail Box

................................................................................................................ Item Number: 40155   Enlarge Backup Parking Sensor System with 4 Rear In-Bumper Sensors. Sensor Color: Silver. Wireless LED Display with Built in Audible Alert with On/Off Switch. R4BWS-40155   US$ 39.75 Choose Quantity 1 2 3 4 5   In Stock. Usually ships within 1-2 business days.     Note: to estimate shipping and handling cost, add the item to your shopping cart, proceed to Check Out, enter your shipping address, and submit the form.