A simple reminder to keep a switch in a fixed position, either ON or OFF.
Some switch protectors put a cowling over the entire switch. This has the advantage of making it much more difficult to accidentally change the position of the switch, but the cowl also hides the actual position of the switch. There's a similar-looking device on the market that doesn't have the "step"; that means it won't work on some installations where this one will work.
Sometimes you have things like motion-sensing security lights, surveillance cameras, computers, etc. that are on switched circuits. This simple little reminder helps prevent accidental changes of switch position.
This invention is not patented, and won't be. Although there is no volume manufacturer, I can print one for you on my 3D printer. The actual product won't be as slick and glossy as this computer rendering, but it will be reasonable-looking and serviceable. The cost will be $1 plus shipping; email me using the email form on the home page.
I call this device a "reminder" not a "lock" because it is easily turned aside, even by a child. Therefore, it is NOT suitable for use where any safety hazard would be introduced if the switch changes position.