diff --git a/FModel/ViewModels/CUE4ParseViewModel.cs b/FModel/ViewModels/CUE4ParseViewModel.cs
index 7586ab9f..2203df3f 100644
--- a/FModel/ViewModels/CUE4ParseViewModel.cs
+++ b/FModel/ViewModels/CUE4ParseViewModel.cs
@@ -763,7 +763,8 @@ public class CUE4ParseViewModel : ViewModel
             }
             case UMaterialInstance m when ModelIsOverwritingMaterial:
             {
-                throw new NotImplementedException();
+                SnooperViewer.SwapMaterial(m);
+                return true;
             }
             case UStaticMesh when UserSettings.Default.SaveStaticMeshes:
             case USkeletalMesh when UserSettings.Default.SaveSkeletalMeshes:
diff --git a/FModel/Views/Snooper/Options.cs b/FModel/Views/Snooper/Options.cs
index 19ab5a59..80e93c40 100644
--- a/FModel/Views/Snooper/Options.cs
+++ b/FModel/Views/Snooper/Options.cs
@@ -11,6 +11,9 @@ public class Options
     public int SelectedSection { get; private set; }
     public int SelectedMorph { get; private set; }
 
+    public bool Append { get; set; }
+    public bool Close { get; set; }
+
     public Options()
     {
         Reset();
@@ -22,6 +25,8 @@ public class Options
         SelectedModelInstance = 0;
         SelectedSection = 0;
         SelectedMorph = 0;
+        Append = false;
+        Close = false;
     }
 
     public void SelectModel(FGuid guid)
@@ -49,4 +54,9 @@ public class Options
             section = model.Sections[SelectedSection]; else section = null;
         return section != null;
     }
+
+    public void SwapMaterial(bool value)
+    {
+        Services.ApplicationService.ApplicationView.CUE4Parse.ModelIsOverwritingMaterial = value;
+    }
 }
diff --git a/FModel/Views/Snooper/SnimGui.cs b/FModel/Views/Snooper/SnimGui.cs
index f40c7e6b..17457ff2 100644
--- a/FModel/Views/Snooper/SnimGui.cs
+++ b/FModel/Views/Snooper/SnimGui.cs
@@ -293,9 +293,7 @@ public class SnimGui : IDisposable
                     {
                         options.SelectSection(i);
                         if (ImGui.Selectable("Swap"))
-                        {
-
-                        }
+                            options.SwapMaterial(true);
                         if (ImGui.Selectable("Copy Name to Clipboard"))
                             Application.Current.Dispatcher.Invoke(delegate
                             {
diff --git a/FModel/Views/Snooper/Snooper.cs b/FModel/Views/Snooper/Snooper.cs
index b29064b0..e39e01a4 100644
--- a/FModel/Views/Snooper/Snooper.cs
+++ b/FModel/Views/Snooper/Snooper.cs
@@ -49,7 +49,6 @@ public class Snooper
 
     private Vector2D<int> _size;
     private float _previousSpeed;
-    private bool _append;
 
     public Snooper()
     {
@@ -206,9 +205,19 @@ public class Snooper
         DoLoop();
     }
 
+    public void SwapMaterial(UMaterialInstance mi)
+    {
+        if (!_models.TryGetValue(_options.SelectedModel, out var model) ||
+            !_options.TryGetSection(model, out var section)) return;
+
+        section.SwapMaterial(mi);
+        _options.SwapMaterial(false);
+        DoLoop();
+    }
+
     private void DoLoop()
     {
-        if (_append) _append = false;
+        if (_options.Append) _options.Append = false;
         _window.Run();
         // if (_window.IsInitialized)
         // {
@@ -376,7 +385,7 @@ public class Snooper
             // we can't use GLContext back on next load and so, for now, we basically have to reset the window
             // if we can't use GLContext, we can't generate handles, can't interact with IsVisible, State, etc
             // tldr we dispose everything but don't clear models, so the more you append, the longer it takes to load
-            _append = true;
+            _options.Append = true;
             _window.Close();
             // _window.IsVisible = false;
         }
@@ -395,7 +404,7 @@ public class Snooper
         {
             model.Dispose();
         }
-        if (!_append)
+        if (!_options.Append)
         {
             _models.Clear();
             _options.Reset();