Classic Mercedes headrest, introduced in 1968, used on all Mercedes cars until 1979. Changed over for the 1980 model year to the smaller, so-called ‘biscuit’ style.
All cars, except for the W116 and the W100.
The W116 lingered into 1980 for US sales only, and D-B didn’t see the need to change over.
The W100 was very limited production by that time, and only 64 examples were produced in 1980 and 1981 with the old style headrest.