<ComboBox x:Name="Customer"
              Grid.Column="1"
              Grid.Row="1"
              IsReadOnly="True"
              DisplayMemberPath="cust_name"
              ItemsSource="{Binding Customers}"
              SelectedItem="{Binding SelectedElementCustomers}"
              Style="{StaticResource ComboBoxStyle}"
              BorderBrush="{StaticResource brushWatermarkBorder}"/>