Searching for a maximum part rotation script? (NO REQUEST)

First off this is ->NOT<- meant to be a "script it for me "request it is only a searching request

->cause iam a german and have no clue on how to call the script that iam searching for .

:So iam searching for a script which prevents a part from rotating further than 50 degrees up and down so that it cannot flip over ;

-> Does somebody know a script like that or can someone atleast tell me on how such a kind of script could be told ?

Thanks for any help (: