@Override
  public void addInformation(ItemStack is, EntityPlayer ep, List li, boolean vb) {
    super.addInformation(is, ep, li, vb);

    if (is.stackTagCompound != null) {
      Coordinate loc = Coordinate.readFromNBT("target", is.stackTagCompound);
      if (loc != null) {
        li.add("Linked to: " + loc.toString());
      }
    }
  }
 @Override
 public void getSubItems(Item item, CreativeTabs c, List li) {
   super.getSubItems(item, c, li);
   li.add(new ItemStack(this, 1, 1));
 }