This is the seat adjusting hardware for a Model B Fordor sedan. The handle is nickel plated zinc die cast.
The ratchet bracket was missing from my car and was rather elusive to find. The scan is from the Hardware and Trimming catalog, and shows the other body models which also used it.
The bracket on the left is the typical body mounted bracket used on late 1931 Model A's. The bracket on the right is 1932.
Pic above shows two styles of ratchets. These were used on both 1931 Model A's and on Model B's. Upper one has round mounting holes and lower has square holes.