The EVVA 3KS is a high security lock, it uses a simple mechanism but has very high pick resistance. The lock uses a slider system, using 12 sliders, 6 on each side. The key is reversible, and has 3 curves on each side as well as a ‘profile‘ on the top and bottom. 2 of these curves are identical and the third is different, this is because on one side of the lock the sliders have 2 ‘posts’ sticking out of them, and the other sides sliders have 1 ‘post’ on it. On the sliders with the 2 posts, the posts are shorter than the other sliders, this way the single post sliders wont go into the double post sliders curve. The plug looks very unique, it has 12 slots for the sliders as well as slots for the sidebars. The way this lock operates is quite simple, the key is inserted and the posts on the sliders follow the curves on the key. The back of each slider has 2 small notches in it that the sidebar can fall into, once the slider is properly positioned. When the correct key is inserted, all the notches line up and the sidebars fall into them and the lock opens. You may notice that a couple of the sliders stick out of the plug a little, the housing is milled so that the sliders can stick out of the plug a little, and the lock will still be able to function properly. When an incorrect key is inserted, the notches don’t line up and the sidebar can not fall down, and thus the lock does not open. The profile markings on the top of the keys interact with a passive bar on the top of the lock. When the correct key is used, the profile bar falls into the markings on the key, and the lock will not be impeded by it. However, if you grind down the marking on the top of the key, then the profile bar is not a problem because there is nothing there to get in the way of the bar. When dissassembling the lock it is best to insert the key and then slowly pull it out, DO NOT force the cylinder out because you will ruin the milling in the housing as well as possibly break a slider. The key image with the colored curves was taken by n2oah, I tried for quite some time to make a similar one that looked decent, but I just couldn’t.