diff --git a/gui.glade b/gui.glade
index 403de84..48ec056 100644
--- a/gui.glade
+++ b/gui.glade
@@ -7,6 +7,7 @@
     <property name="title" translatable="yes">Decifra ROTx</property>
     <property name="icon_name">security-medium</property>
     <property name="show_menubar">False</property>
+    <signal name="destroy" handler="on_window1_destroy" swapped="no"/>
     <child>
       <object class="GtkBox" id="box1">
         <property name="visible">True</property>
diff --git a/gui.py b/gui.py
index 30481a3..1e01499 100644
--- a/gui.py
+++ b/gui.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 
-import sys, decifra
+import sys, decifra, string
 import gi
 gi.require_version('Gtk', '3.0')
 from gi.repository import Gtk
@@ -29,7 +29,7 @@ class DecifraGui:
         self.window.set_wmclass("Decifra ROTx", "Decifra ROTx")
         self.testocifrato = self.builder.get_object("fldTestoCifrato_in")
         self.rotazione = self.builder.get_object("fldRotazione_in")
-        adj = Gtk.Adjustment(1, 1, 99, 1, 1, 1)
+        adj = Gtk.Adjustment(1, 1, len(string.ascii_uppercase), 1, 1, 1)
         self.rotazione.configure(adj, 1, 0)
         self.risultato = self.builder.get_object("lblRisultato")
         self.risultato.hide()