Two important differences between the Tesla plug design and J-1772 is that with the Tesla the locking mechanism is in the vehicle, controlled by the vehicle electro-mechanically. With the J-1772 design it is on the cord, thus will get more use cycles per time period for charging locations used by multiple vehicles. The J-1772 also uses just spring loaded clip that is further off-center of the plug. It isn’t as secure a design.