 Hi there, this is Alex, I was putting away this Tesla lock that I got from Bosnian Bill and because it happened to be broken in half, here's the other half, that Bill milled open in probably to punish the lock for not opening, I thought I'd realized in the bag of parts I had all of the bits of the cam and there was a discussion about bypassing euro cylinders and cams and so forth, so I thought I'd shoot a quick video on how that might work, on how the at least a cam system here works. So what you see here is the inside of the cylinder that keeps back here, this is the rear of the plug and there's a deep hole in there and if I push the key all the way in, if you can see real well, but a bit of the key extends into the cylinder, you can see it right there at the top. So how does this work? Well we know that in the middle of the lock there's this cam and this cam is what actuates the actual lock in the door or whatever fitting it's in. And there are two sides to the lock and typically only one of them is unlocked at a time, right? So the cam cannot be engaged with both sides of the lock or it would never be able to move unless they were both unlocked and that's not the situation we're in. So there's a mechanism in here that allows it to select which side, which cylinder is activating it and the way it works is there's this, in this particular implementation there's this little pin, you see that little pin that goes down inside here like that and then the cam would sit on here between the circlips which we all love and then there's this little double cam looking thing and these bits spin independently, okay? So there's two of these, one for each side and these go into here, there we go and they engage with these little slots in the rear of the plug when the plug turns around. So as it is right now it can spin freely because neither end is engaged and when we don't have this end. But let's say that we want to unlock this side of the door so when I pull the key out this thing can go back in, right? Push the key in, that pops out, hopefully that's visible, okay? Now once that's popped out two things happen. This part on the end is now can now spin freely which means it's no longer engaged with the other cylinder which would be blocked, okay? And now it's also made sure that the cam is engaged with this cylinder and can rotate it and so now we can unlock the door, okay? Great. Now a couple things about this design. First thing we notice is that because we have this little plug inside the cylinder, inside the rear of the cylinder, okay, here's the other side. Because we have this little plug in here there's no way for Bill to stick his little wire in and manipulate the cam independently. Also the cam is always engaged with one or the other side of the lock via this little spinny bit, right? So even if you pushed it, well you can't push it all the way through but no matter what you do you're engaged with one of the two locked locks and even if the inside is a thumb turn you're not going to be able to really manipulate it because you can't reach in there. So it's a little better design. Another interesting feature is that if I, so the way this would work, let's say we take this key out so we lock up the house and now someone on the inside would like to unlock the lock. So they put their key in, their plunger would push forward into this but it depends on being able to push this guy back in so you'd see how he's inset now, okay, he's back in like maybe a eighth of an inch or something like that. Now let's suppose that someone puts their key in here which, oops, pops that guy out very vigorously, put this back in, sorry for the reach now and say he just turns the cylinder slightly, okay. Now no matter what I do on this side I am not going to be able to push that thing in and I'm not going to be able to get my key engaged far enough in there to activate the bidding. So I can pick this all day long and, well I can pick it open but you know I can fiddle with it with my key all day long and I'm not going to get anywhere. If this happens to be at the, right on the center line so that it's the other ones that cheer, if you push hard enough you can eject the other key and get in. So I presume if you had a double cylinder on a door and you wanted to leave the key in there you need to make sure that you leave it in the vertical position or maybe out one notch so that someone can get in assuming you would like for them to get in, okay. So that's how these things work. I've taken apart a couple of these, they have, I've seen different implementations of this, sometimes the key actually will hook into here, depends on the length and how nicely it's designed. In this particular case it's resistant to that bypass technique that Bosnian Bill showed a week or two ago due to this little plug that's in here. So I thought that was pretty cool and since Bill did sacrifice this lock for the benefit of lock science I thought I'd finish out the topic, be it to death, and show you how that works. So all you guys in Europe are yawning right now or have already turned off the video. Guys in America maybe you find that interesting and maybe it helps you if you're servicing one of these locks or fiddling with it. So there you go, this is Alex, thanks for watching, please subscribe to my channel and as always have fun and keep it legal, cheers.