Here we are looking at the 30A field install/retrofit plug and a 30A inlet. There are FOUR points of positive locking between the inlet and the plug:


#1 Right & left push lock connectors which are similar to the locking mechanisms found in cordless drill batteries. They are SS and lock into very thick and robust notches in the sides of the inlet.


#2 The front portion of the lid, nearest the hinge, positively locks into the plug body.


#3 The back portion of the lid locks positively into the plug body.


Rather than do my own video SmartPlug has already done this: