Backing Up Alert Devise

[Ritzinger]

There is a device for sale on line www.skymall.com called auto alert its $39.95 and it plugs into reverse lights and (looks like from the picture) attached to the rear tag's. When you put your vec in reverse, the closer you get to something, in the back, the louder a audible detection becomes.

Any body had any experiece with this or similar product?

[SKperformance]

i could not find it ,it is better to post a link next time to save others from searching an entire site to help

Their are nice systems wwith audible and visual led bars to tell the distance for about 60-70