Bloccaggio in acciaio

   *****    *****       *    ******   *******  ******   
  *     *  *     *     **    *     *       *   *     *  
  *     *  *     *    * *    *     *      *    *     *  
   ******   ******   *  *    ******      *     ******   
        *        *  *******  *     *    *      *     *  
       *        *       *    *     *   *       *     *  
   ****     ****        *    ******   *        ******