The Boeing 737 MAX will soon be back y, following a 20-month grounding. American Airlines is expected to be the first U.S. airline to return the troubled aircraft to service, with flights starting December 29. However, passengers may not be able to easily tell which plane version they’re flying on, as some airlines are dialing back usage of the MAX name. We’re here to help.

The 737 MAX was grounded after two fatal crashes. In 2018, Lion Air Flight 610 crashed in Indonesia, killing 189. Five months later, Ethiopian Airlines Flight 302 crashed in Ethiopia, killing 157. The result of these crashes was a scandal and a nosedive in trust in . What followed was almost two years of fixing the aircraft’s deadly flaws, testing and ultimately recertification.

In , some airlines are said to be pulling back usage of the MAX name in reference to the airliner. Sources familiar with the situation say airlines may slowly phase out the MAX name in favor of the model name without the MAX branding: 737-7 or 737-8 as an example.

Passengers looking into American Airlines flights should see the MAX name on booking systems, however .

A spokeswoman for American says the change is to standardize safety cards across the 737 models. Via :

This approach is consistent with other fleet types where we do not have different safety cards for sub-fleets.

To be fair to American, Southwest didn’t remove the MAX from its safety cards , after passenger raised concerns. Still, I feel like there’s a better method to alleviate fears than simply scrubbing MAX from the documentation.

Last year, Forbes that even before the MAX crashes, not every airline clearly marked each plane as a MAX. From :

Of the 54 airlines that have 737 MAXs identifiably painted, only 11 airlines consistently write “MAX” on the aircraft’s nose, likely the most obvious physical indicator to passengers if their 737 is a MAX. A further 26 airlines put “MAX” only at the aircraft’s rear while 13 airlines have no markings mentioning the aircraft type at all. Three airlines say 737-8 without mentioning MAX, while Ryanair has inconsistent practices.

So you may wonder, how can you tell if you’re flying on a 737 MAX today?

Well, it depends on how low-key the airline will be about the MAX naming. First, check the booking information. Sometimes before you even book a flight you can see what kind of plane will be used. If your booking information doesn’t note what kind of 737 you’ll be flying, you may be able to spot the naming on the nose, tail or landing gear doors. Some airlines with a high number of 737 MAX aircraft orders, like Southwest, have no prominent markings at all.

At the airport, you can also check at the end of the wings. The 737 MAX will often have winglets that extend both up and down. Other versions of the 737 often have winglets that extend only upward. However, as some airlines — like United — have upgraded older planes to use the newer winglets, this isn’t always a surefire way to determine 737 type, either.

If all else fails, look at the engines. The 737 MAX uses .

These are physically larger and pushed forward compared with the of the older 737NG. The LEAP-1B engines will also have serrated edges at the rear of the engines.