diff --git a/Samples/Views/MainView.xaml b/Samples/Views/MainView.xaml
index 18f7c77d0f3f2f40e42022b6a16eb85c48c74b7d..150827a090fa53e489ca9faa6f7a15290e2e2527 100644
--- a/Samples/Views/MainView.xaml
+++ b/Samples/Views/MainView.xaml
@@ -124,5 +124,7 @@
                            Text="{Binding Now, Source={x:Static pu:Tools.DateTime}, StringFormat='MM/dd/yyyy HH:mm:ss'}" />
             </Grid>
         </Grid>
+        <pu:NumberInput Maximum="20"
+                        Interval="4" />
     </Grid>
 </pu:WindowX>
\ No newline at end of file
diff --git a/SourceCode/SharedResources/Panuon.WPF.UI/Controls/NumberInput.cs b/SourceCode/SharedResources/Panuon.WPF.UI/Controls/NumberInput.cs
index 2389b99088ab28fd98b2f215caeab362c84acec1..88f56bb283fc25e7363534d00cb7a9b6055463b9 100644
--- a/SourceCode/SharedResources/Panuon.WPF.UI/Controls/NumberInput.cs
+++ b/SourceCode/SharedResources/Panuon.WPF.UI/Controls/NumberInput.cs
@@ -428,12 +428,12 @@ namespace Panuon.WPF.UI
         #region Methods
         public void Up()
         {
-            SetValue(ValueProperty, Value + Interval);
+            SetValue(ValueProperty, Math.Max(Minimum, Math.Min(Maximum, Value + Interval)));
         }
 
         public void Down()
         {
-            SetValue(ValueProperty, Value - Interval);
+            SetValue(ValueProperty, Math.Max(Minimum, Math.Min(Maximum, Value - Interval)));
         }
         #endregion
 
diff --git a/SourceCode/SharedResources/Panuon.WPF.UI/Properties/AssemblyInfo.cs b/SourceCode/SharedResources/Panuon.WPF.UI/Properties/AssemblyInfo.cs
index a33a2e7b556f024cb5a3286cd17e48cc26f5eb05..165d439dda7780bd19aa601bfb27e5023ba75cc8 100644
--- a/SourceCode/SharedResources/Panuon.WPF.UI/Properties/AssemblyInfo.cs
+++ b/SourceCode/SharedResources/Panuon.WPF.UI/Properties/AssemblyInfo.cs
@@ -20,5 +20,5 @@ using System.Windows;
     ResourceDictionaryLocation.SourceAssembly
 )]
 
-[assembly: AssemblyVersion("1.1.9.1")]
-[assembly: AssemblyFileVersion("1.1.9.1")]
\ No newline at end of file
+[assembly: AssemblyVersion("1.1.9.2")]
+[assembly: AssemblyFileVersion("1.1.9.2")]
\ No newline at end of file