When Chrysler changed the design of its digital neutral safety switch, the case hole was made larger. These late-model Chrysler 42RE, 44RE, 46RE and 47RE cases could not be used for applications requiring the early-style neutral safety switch. Sonnax neurtral safety switch adapter kit 22179-06K screws into a late-style case and when used with an earlier style valve body manual lever, allows these cases to be used in earlier model vehicles. Drop-in Zip Valve™ parts install quickly and easily.