I GOT INTO MY CAR AND TURNED ON THE SEAT WARMER. AFTER 10 MINUTES OF DRIVING ON THE HIGHWAY I COULD SMELL SMOKE BUT THOUGHT IT WAS OUTSIDE THE VEHICLE. A FEW SECONDS LATER I FELT A BURNING SENSATION ON MY LOWER BACK. I REACHED MY LEFT HAND BEHIND ME TO CHECK AND FELT SOMETHING HOT, WHEN I PULLED MY HAND OUT MY FINGER TIPS WERE COVERED IN MELTED LEATHER. THE SMOKE BY THEN INCREASED, I SHUT THE SEAT WARMER OFF AND EXITED THE HIGHWAY AS QUICKLY AS POSSIBLE.