Contractible Plug / Plug

We have such annoying experience as our outlet plug cannot match the socket on the wall. We will look for the outlet plug adapter or choose to break off the third prong under such circumstance.
If the third prong is contractible, it would remain intact as we plug into socket with three holes. When we plug into the socket outlet with two holes, the third prong will contract as it faces the resistance.
The design of this outlet plug equipped with the rebound spring behind the third prong. As the resistant force is larger than the pushing force, the ground prong will be shifted inside the outlet plug due to the spring mechanism.