using sleeves, rings or the like, as main fixing elements

Full Title

Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00 > Mining picks; Holders therefor (planing knives E21C27/44) > Means for fixing picks or holders > using sleeves, rings or the like, as main fixing elements