Propeller Mechanical Protractor

The listing

First of all I'm located in Colorado. Have a superb condition Propeller Mechanical Protractor w/ Original box which I got from my now late father-in-law who worked for Bell helicopter. He also built his own aircraft. Comes with original box designated by the FSN & amp; Model number. Found a similar protractor listed for $880.oo. Taking the highest bidder over $575. May take trades. No low ballers. They'll be ignored. Hoping for a true user or collector. I will not take checks or a so called friend coming to pick it up. Cash is it or a TRUE Bankers check. No third party help. Marshall