The seats are most definitely leather, I actually pulled the seat backs off while the seats where still in the car to get to the material's edge to have a look and be certain. The only reason I even bothered to get them is that they where in excellent shape, had heaters and where leather. Its the only heated 123 seats I've ever seen, I have never seen or heard of heated MB Tex, I see lots of 126, quite a few 124, and a couple of 201 heated seats. As a matter of fact I recently pulled a pair of Palomino colored electrically adjustable leather seats for my own 201 project that are not only heated but also are equipped with multi-zone orthopedic pneumatic lumbar supports! I was also able to get the special door lock pump that has an additional pressure outlet to provide inflation for the lumbar bladders. So eventually, I'll be riding high!! Well thanks for asking, if you did.