This video I put together just recently, it's a video on a very basic piston contraption that I came up with, it's probably already thought of but I haven't found any videos on it so I decided to make one. Very simple video to understand and follow, straight forward no trickery. Also please remember this was filmed in one take so it's not perfect footage. 

Here is the video anyway, please enjoy. If you like the video and thought it was useful feel free to hand me one of your thumbs it just gives me more popularity and determination to make more tutorial videos at the end of the day it helps both of us.

This is a simple piston project. Takes less then a few minutes to complete, very effective I use this a lot on PVP servers with no chest protection plugins.