This is a genuine BMW tension strap inner left, part number 16 11 1 180 452. The number stamped on the part is 16111180452; BMW's catalog files it under the short number 1180452. You will find it on our Fuel System shelf, under Fuel tank with filler pipe. It supersedes the older number 1181431, so a part carrying that number is the same part.
It fits the E36 sedan, coupe, convertible and touring (318i, 320i, 323i, 325i and 328i, 1992–1999), with the M40, M42, M43, M44, M50 or M52 engines — and the European-market versions.
BMW draws it on the Plastic fuel tank (16_0314) diagram. It weighs about 394 g (0.9 lb).
We have not had one on the shelf yet. Request it and we will tell you when one comes off a car.