3-Arm - Self-centering MECHANICAL PULLERS BETEX 52 Patented self-centering 3-arm pullers (mechanical and hydraulic) for ø40 mm through ø640 mm. The 3 arms of these pullers adjust themselves simultaneously and symmetrically, inwards or outwards. There is no possibility of the arms bending or deflecting. Hydraulic screws with a 20-ton capacity are available for use in combination with the two largest pullers. The thread of the screws is in no way affected by the build up of hydraulic pressure, thus keeping wear and tear of the screws down to a minimum.