Tool used to check the steering on aircraft.  Wish I had this labor saving tool when I was an A&P

To use:  Jack the nose of the aircraft up high enough to slip the protractor under the tire, lining up the rectangular slot to the tire.  Lower the nose of the aircraft onto the protractor and loosen the screws on the side to adjust the protractor to zero when the nose steering is in the neutral position.  Always use the maintenance manual for that particular aircraft for complete instruction.  My instructions are generic and you must first follow the manual.