Seco Side Lock Holder for Weldon shanks are simple to use and provide safe and strong clamping with a strong anti-pulling action. The EPB 584 type has a fixed tool position as a result of the tool shank flats and cannot be adjusted. The locking method offers high torque transmission. Additionally, EPB 5842 has a short design, giving maximum rigidity. Direct run-out of the bore to the external taper is 5 um. Reduced bore tolerances are 1 to 5 um on 6 to 18 mm Dia and 1 to 7 um on 20 mm Dia.