diff --git a/.gitattributes b/.gitattributes
index 8abc5e3..b401c91 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -113,6 +113,7 @@ invesalius/gui/__init__.py -text
 invesalius/gui/data_notebook.py -text
 invesalius/gui/default_tasks.py -text
 invesalius/gui/default_viewers.py -text
+invesalius/gui/dialogs.py -text
 invesalius/gui/frame.py -text
 invesalius/gui/import_data_wizard.py -text
 invesalius/gui/import_panel.py -text
diff --git a/invesalius/gui/dialogs.py b/invesalius/gui/dialogs.py
new file mode 100644
index 0000000..8c28cf1
--- /dev/null
+++ b/invesalius/gui/dialogs.py
@@ -0,0 +1,59 @@
+import wx
+from wx.lib import masked
+
+class NumberDialog(wx.Dialog):
+    def __init__(self, message, value=0):
+        pre = wx.PreDialog()
+        pre.Create(None, -1, "InVesalius 3", size=wx.DefaultSize, pos=wx.DefaultPosition, 
+                    style=wx.DEFAULT_DIALOG_STYLE)
+        self.PostCreate(pre)
+
+        # Static text which contains message to user
+        print "message: ", message
+        label = wx.StaticText(self, -1, message)
+
+        # Numeric value to be changed by user
+        num_ctrl = masked.NumCtrl(self, value=value, integerWidth=3,
+                                    fractionWidth=2, allowNegative=True)
+        self.num_ctrl = num_ctrl
+
+        # Buttons       
+        btn_ok = wx.Button(self, wx.ID_OK)
+        btn_ok.SetHelpText("Above value will be applied.")
+        btn_ok.SetDefault()
+
+        btn_cancel = wx.Button(self, wx.ID_CANCEL)
+        btn_cancel.SetHelpText("Value will not be applied.)")
+
+        btnsizer = wx.StdDialogButtonSizer()
+        btnsizer.AddButton(btn_ok)
+        btnsizer.AddButton(btn_cancel)
+        btnsizer.Realize()        
+
+
+        sizer = wx.BoxSizer(wx.VERTICAL)
+        sizer.Add(label, 0, wx.ALIGN_CENTRE|wx.ALL, 5)
+        sizer.Add(num_ctrl, 0, wx.ALIGN_CENTRE|wx.ALL, 5)
+        sizer.Add(btnsizer, 0, wx.ALIGN_CENTER_VERTICAL|wx.ALL, 5)
+
+        self.SetSizer(sizer)
+        sizer.Fit(self)
+
+        self.Centre()
+
+    def SetValue(self, value):
+        self.num_ctrl.SetValue(value)
+
+    def GetValue(self):
+        return self.num_ctrl.GetValue()
+
+def ShowNumberDialog(message, value=0):
+    dlg = NumberDialog(message, value)
+    dlg.SetValue(value)
+
+    if dlg.ShowModal() == wx.ID_OK:
+        return dlg.GetValue()
+    dlg.Destroy()
+
+    return 0
+
--
libgit2 0.21.2