In this lesson, we'll create the mounting holes for the component tray. After completing this lesson, you'll be able to create a sketch circle, use Fillet, and extrude through multiple bodies. Carrying on with a file from our previous example, we want to do a little bit more detail work on the component tray. So far, we've added all the geometry to hold the flight controller, the power distribution board, the controller receiver, and the ESCs. We still need to have a way to get cables into and out of this area and we need to do a little bit of cleanup work as well. We have to create our bolt holes and we want to make sure that we have all the geometry needed in order to hold the batteries. So I'm going to start by creating a Fillet on these corners of five millimeters and that way I don't have any sharp external corners. I can do this on the inside as well. But on the inside, it looks like this could potentially cut into a lot of area that is needed. So on the inside, if I add Fillets I'm going to probably create a much smaller radius Fillet. So, we'll say OK, we'll repeat the command, and on the inside edges let's go ahead and add a one-millimeter Fillet. Sometimes, it helps to rotate this around and select it while you're looking at the edges because when you're selecting through geometry there are a lot of other edges that can get in the way of the selection process. We'll say one millimeter and this looks like it leaves enough room for the capacitor on the end of the ESC. Next, let's go and rotate this around and we're going to select one of the counter bore faces to start a new Sketch. We're going to be creating a five and a half millimeter circle at the center. That's going to give us enough clearance for a five-millimeter screw. Now, you notice that I can't snap to the center point of the other circles. Because I selected this face to start my Sketch it was able to snap to the center point. In order to get the other holes, I will have to use project and then I can play circles at each one of their center points. I then want to make sure that I have all four of these equal. And I'll start by selecting the Equal Constraint first and going around one by one and selecting each of these. I do want to note also that instead of pre-selecting Equal, I can pre-select all the holes and then press Equals and it'll create Equal Constraint at that time. I want to stop the Sketch and I want to make sure that I expand the bodies and show the XStar body. We're going to create an extrude. We're going to make sure that we select all four of the holes. And we're going to extrude those up through the component tray as well as the XStar body and notice that objects to cut will go through both of those and we can say OK. Next, we're going to rotate this around and make sure that the holes are cut through the top. We will be creating a hex recess in the top here. In that way we can drop a nut in the top and when we screw the bottom in we have a metal thread in the plastic. And you could do this multiple ways and I mentioned using hot melt inserts or other various fasteners. And in this case, I want to make sure that we avoid using thread-forming screws that are typically used in plastic applications because the component tray is going to be going on and off several times. I also want to make one more note about the flight controller. We're going to have to plug a USB cable in when we program the flight controller. Now, that's going to be plugged in and then the flight controller and the entire component tray will be assembled. But in this case, that cable can actually come out of this recess or this opening. And that way we can have the vehicle fully assembled and still program it. We will have to disassemble the component tray to unplug the cable, but it gives us a good accurate setting for setting up the flight controller to be level as well as testing out all the ESC's motors. So, now there is some additional things that we need to do. We need to handle cables coming into and out of and we need to talk about the additional structure and mounting point that we have. I want to make sure that I leave the structure off coming from the component tray to this mounting point until we do a simulation of the entire design. I want to avoid adding additional material unless I absolutely have to. In this case, I want to leave the mounting point here, but I'm not going to create any geometry to mount to it until I'm sure that the design needs the additional structure. So while I do have that point created, I am going to leave it for right now.