diff --git a/gui/ModifyParameters.py b/gui/ModifyParameters.py
index ead4280..648316f 100644
--- a/gui/ModifyParameters.py
+++ b/gui/ModifyParameters.py
@@ -69,7 +69,7 @@ def create_element(self, param, row):
 
             else:
                 try:
-                    entry = ttk.Entry(self.root)
+                    entry = tk.Entry(self.root)
                     if param != 'size':
                         if param in ['reflection_factor', 'transmittance']:
                             entry.insert(0, f'{str(self.parameters_dict[param] * 100)}%')  # Set default value in percentage