Multiple custom field values

I created meta box and added custom field with key “roomtypes”.
My custom filed “roomtypes” will have some values.

So i will have one key and several values.

Is it possible to make button like “add one more text field”, like in plugin Custom Field Template?

To clear what i mean:

$roomtypes  = get_post_meta($post->ID, 'roomtypes', false); 
      $sb_label = 'Room Type';
      foreach($roomtypes as $roomtype) {
      $sb_label .= '#' . $roomtype;
      }