The NTSB has released the image below of the MAX 9 Exit Door showing its complexity and number of secure points.
Each MAX 9 Door Exit is held in place by a wide range variety of mechanisms which are shown below on the diagram.
The pressure load is carried by 12 doorsteps with six on each side.
The are significant differences in the Boeing 737 MAX exit doors plus earlier versions of the 737.
The Boeing 737 MAX 9 involved in the exit door incident is a longer model than the standard -8 model, or the yet-to-certified – 7 model and requires read more ⇒
Source:: AirlineRatings.Com