diff --git a/demo/Ursa.Demo/Pages/ClassInputDemo.axaml b/demo/Ursa.Demo/Pages/ClassInputDemo.axaml
index fc51e6d..344b77e 100644
--- a/demo/Ursa.Demo/Pages/ClassInputDemo.axaml
+++ b/demo/Ursa.Demo/Pages/ClassInputDemo.axaml
@@ -6,7 +6,7 @@
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
              x:Class="Ursa.Demo.Pages.ClassInputDemo">
     <StackPanel HorizontalAlignment="Left" Spacing="20">
-        <u:ControlClassesInput Name="input" />
+        <u:ControlClassesInput Name="input" Separator=" " />
         <Button u:ControlClassesInput.Source="{Binding #input}" Content="Hello Panda" />
         <Button u:ControlClassesInput.Source="{Binding #input}" Content="Hello Panda" />
         <Button u:ControlClassesInput.Source="{Binding #input}" Content="Hello Panda" />
diff --git a/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml b/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
index f7b7bb0..3f5f640 100644
--- a/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
+++ b/src/Ursa.Themes.Semi/Controls/ControlClassesInput.axaml
@@ -7,7 +7,11 @@
         <Setter Property="Width" Value="200" />
         <Setter Property="Template">
             <ControlTemplate TargetType="u:ControlClassesInput">
-                <u:TagInput HorizontalAlignment="Stretch" AllowDuplicates="False" Tags="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TargetClasses, Mode=TwoWay}" />
+                <u:TagInput
+                    HorizontalAlignment="Stretch"
+                    AllowDuplicates="False"
+                    Separator="{TemplateBinding Separator}"
+                    Tags="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=TargetClasses, Mode=TwoWay}" />
             </ControlTemplate>
         </Setter>
         <!--
diff --git a/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs b/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
index 9966c06..78cf60d 100644
--- a/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
+++ b/src/Ursa/Controls/ControlClassesInput/ControlClassesInput.cs
@@ -24,6 +24,15 @@ public class ControlClassesInput: TemplatedControl
         set => SetValue(TargetProperty, value);
     }
 
+    public static readonly StyledProperty<string> SeparatorProperty =
+        TagInput.SeparatorProperty.AddOwner<ControlClassesInput>();
+
+    public string Separator
+    {
+        get => GetValue(SeparatorProperty);
+        set => SetValue(SeparatorProperty, value);
+    }
+
 
     private ObservableCollection<string> _targetClasses;
 
@@ -44,7 +53,7 @@ public class ControlClassesInput: TemplatedControl
 
     static ControlClassesInput()
     {
-        TargetClassesProperty.Changed.AddClassHandler<ControlClassesInput, ObservableCollection<string>?>((o,e)=>o.OnClassesChanged(e));
+        TargetClassesProperty.Changed.AddClassHandler<ControlClassesInput, ObservableCollection<string>>((o,e)=>o.OnClassesChanged(e));
         SourceProperty.Changed.AddClassHandler<StyledElement, ControlClassesInput?>(HandleSourceChange);
     }
 
@@ -67,8 +76,6 @@ public class ControlClassesInput: TemplatedControl
             newControl._targets.Remove(oldControl);
         }
     }
-
-    private static readonly char[] _separators = {' ', '\t', '\n', '\r'};
     
     private void OnClassesChanged(AvaloniaPropertyChangedEventArgs<ObservableCollection<string>?> args)
     {