07370428 is referenced by 6 patents and cites 25 patents.

A potential parking area level indicator is provided that includes a centralized hub with a plurality of arms depending therefrom. Preferably, four arms are provided that are spaced 90 degrees from each other thereby defining two sets of opposing arms. In operation, a driver of an RV would locate the level indicator on a potential parking area thereby placing the arms onto the potential parking surface. If the line defined by a pair of opposed arms is placed on a generally level area, indicator lights will illuminate indicating that fact. If, however, the line defined by opposing arms is placed on a grade that is not acceptable for parking, the indicator lights will not illuminate showing that the potential parking area is unsafe for parking. Proper illumination of the lights is driven by accelerometers incorporated into the arms of the level indicator.

Title
Parking area level indication device
Application Number
11/422345
Publication Number
7370428 (B2)
Application Date
June 6, 2006
Publication Date
May 13, 2008
Inventor
Daniel L Decker Jr
Castle Rock
CO, US
Agent
Sheridan Ross P C
Assignee
B & D Manufacturing
CO, US
IPC
G01C 9/06
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