Ladder safety lelel ('LSL')

A safety device for non-self supporting ladders, straight or extension, which provides the user exact indication when the correct and legal ladder inclination is achieved at set-up and during ladder use allowing safe climbing or descent of the ladder. The device color is a visual safety prompt on the exterior of the ladder and provides supervisory monitoring. Said safety device is automatically self-calibrating and permanently calibrated in the ladder with a revolutionary easy nontechnical insertion into the rung opening located on the side of ladders. The device uses a simple bubble level inside a revolutionary housing whereas when the bubble is inside the lines of the level, the ladder is at a safe inclination and the rungs are level. The safety device does not require specific language knowledge, is independent of ladder length, user characteristics, user training, user knowledge and does not affect whatsoever any other ladder functions.