In this lesson, we'll be creating a surface to trim our generative design. After completing this lesson, you'll be able to create an offset surface. The last step that I want to do in terms of setting up to make our generative mesh wing or mesh that's going to go above these components is to create an offset surface from the original body where we're going to trim. So we're going to turn on the x-star body, and notice that we're only drawing one of these, and we're only drawing one of these because this is obviously a complete mirror or mirroring across the front plane, and this helps with the modeling process because we only have to draw everything once and we can either mirrored across the front plane or mirror it across the right plane and get the same thing. So with this design, we actually could simply model half of it and mirror it across the right plane and then mirror it across the front. But in this specific case, it makes more sense for us to model left and right because we're making use of actually creating the geometry in the sculpt environment, and that'll make a bit more sense when we get to that portion of it. But now, what I'd like to do is come into create and create an offset. What we're going to do is we're going to offset these inside faces, and notice that it automatically change the selection up to this midpoint where the tangency stops because chain selection is turned on. Now, I'm actually going to do minus one millimeters on this, which will put us in the middle of that solid wall. So this will allow us to extend just a little bit past where the solid wall interfaces, and we're going to use this to trim the generative mesh portion of this design. So once we say okay, if we hide the x-star body, I'm going to rename this Gen Mesh Trim, and ultimately what we'll do is we'll use it to do a split body operation under modify, and split any of this solid entities that are on the outside. Because we're designing everything from the top plane and everything is perpendicular or normal to it, we could also just use this same shape and do an extrude cut and join the stuff together, but we don't exactly know which option we're going to do until we actually make the mesh. So right now, we're just going to have this in the file, if we decide not to use it, we can go back and delete it because nothing else will be referenced from it. So everything is good here. I'm going to go ahead and rename these bodies, Gen Mash Top and Gen Mesh Bottom. After I actually make the mesh, we might decide to move the location of those. So for instance, if we look at this from the front, this one is a little bit closer to the middle, while this one's a little bit closer to the top. So for instance, we could come back to this offset surface, and instead of five, we could offset at six millimeters, and then everything updates based on it. Because we took that surface, we mirrored it, we stitched it, and then we projected our sketch onto that surface. So it allows us to update that parametrically. Once we get into the sculpt environment, if we come back and make any changes to that, it will not update those meshes parametrically. So keep that in mind that it's a good idea to make sure that the location of these is right at this point in time. Now, if we go back to sculpt, we can move everything up or down just fine. That's perfectly acceptable, but sometimes it's just easier if we make sure that the setup is okay to start with. We're going to hide the trim surface, and then we'll save the file so that it's ready to move on to the next step.