The housing of a MAF (mass air flow) sensor often has the letters “PBT-GF40” printed on it. Many customers mistakenly think this is a part number and search for things like “air flow meter pbt gf40” or “pbt-gf40 maf”.
However, “PBT-GF40” does not refer to a part number. It simply indicates the type of plastic used for the housing – PolyButylene Terephthalate with 40% glass fiber content. PBT GF 40 natural (6943) is a 40% glass fibre-reinforced, medium-viscosity polybutylene terephthalate (PBT) with very high rigidity and toughness as well as high dimensional and chemical resistance.
PBT-GF40 is commonly used for plastic housings in MAF sensors for newer cars. You will you see it printed on most MAF sensor housings from manufacturers like Bosch or VDO Siemens, regardless of the vehicle make.
The actual OE (original equipment) part number for identifying the correct MAF sensor looks different:

Air flow sensor PBT-GF40
“PBT-GF” on the housing of a MAF sensor

PBT-GF30 and PBT-GF40 are a frequently used plastic for plastic housings and therefore the designation can be found on almost all air flow meter housings from Original equipment manufacturers like Bosch or VDO/Continental or Hella. It does not matter whether the MAF fits for Mercedes-Benz, BMW, Porsche or any other vehicle. If you wish to learn more about this plastic, you can find a data sheet here.

Which number on the MAF is the OE number?

  • For Bosch air flow meters the part number usually looks like this:
    0 280 21x xxx. e.g. Bosch no. 0 280 218 185
MAF sensor for Mercedes-Benz replaces 0280218185 and Mercedes-Benz no. A1560900048
  • VDO/Continental air flow meters stick to the following pattern: 5WKxxxx , e.g. 5WK98101.

MAF sensor 5WK98101 / A 6450900048

  • The newer MAF models of Bosch start with 0 281 xxx like the example below, which shows the Bosch number 0281002954 or 0281002955.
  • BMW original numbers usually start with 1362, e.g. 13627602038.
  • The Mercedes-Benz original numbers for MAF used to begin with “000 094”, e.g. 0000941048.
    But for the newer models the Mercedes number starts with A2760 or A61109 or A65190 or A64590, there are even more variations.
0281002954 or 0281002955
MAF 0281002954/ 0281002955
However, there are often exceptions, so please give us all the numbers that you can find on the mass airflow sensor housing (except of course PBT-GF30 or PBT-GF40 ). Or send us a photo of the old MAF. 
We can also determine the required mass airflow sensor by software based on your vehicle model, but the “part number method” is usually safer.
You can of course also use the vehicle search on our website, which you can find here:
Anyhow the easiest way is to send us an email to or through our contact form.
We will answer your request within 24 hours.