DELCO REMY (GM) neutral safety/backup switch .   It is an OEM USED GOOD WORKING DELCO REMY (GM) switch, not an aftermarket replacement.  The part number is 1998182  it is in GR 4.054 of the GM parts catalogs. Comes in original box and in good clean condition. The part  is stamped 182 Delco Remy on the housing & Delco Remy on the bakelite. Check the part number stamped on your switch.

According to Delco  It  fits: 1955-1956 CHEVROLET CAR w/ PG transmission