diff --git a/core/src/partassembly.h b/core/src/partassembly.h
index 5f899a7..8071a64 100644
--- a/core/src/partassembly.h
+++ b/core/src/partassembly.h
@@ -23,6 +23,7 @@ public:
     inline CFrame assemblyOrigin() { return _assemblyOrigin; };
     inline Vector3 bounds() { return _bounds; };
     inline Vector3 size() { return _size; };
+    inline bool multipleSelected() { return parts.size() > 1; }
 
     // Transforms the assembly such that newOrigin is now this assembly's new assemblyOrigin
     void SetOrigin(CFrame newOrigin);
diff --git a/core/src/rendering/renderer.cpp b/core/src/rendering/renderer.cpp
index c0561e9..07ddcb6 100644
--- a/core/src/rendering/renderer.cpp
+++ b/core/src/rendering/renderer.cpp
@@ -475,11 +475,10 @@ void renderOutlines() {
     }
 
     // Render AABB of selected parts
-    if (count <= 1) return;
-    
-    glm::vec3 outlineSize, outlinePos;
-    outlineSize = (max - min);
-    outlinePos = (max + min) / 2.f;
+    PartAssembly selectionAssembly = PartAssembly::FromSelection();
+    if (!selectionAssembly.multipleSelected()) return;
+    glm::vec3 outlineSize = selectionAssembly.bounds();
+    glm::vec3 outlinePos = selectionAssembly.assemblyOrigin().Position();
 
     glm::mat4 model = glm::translate(glm::mat4(1.0f), outlinePos);
     model = glm::scale(model, outlineSize + glm::vec3(0.1));