This model has no clutch. The approach to the work-piece, before exerting the high pressure, is carried out with a handle. It has an automatic forward and backward movement of 4 mm. This spindle requires an external supply of high pressure oil. In addition the force this spindle provides is directly proportional to the pressure of the external oil. To obtain 4/5/8 ton clamping force, the oil pressure needs to be 500 bar. This is a single acting cylinder and for this reason has only one entry and exit port. This orifice has a rotary adapter to avoid the supply pipe getting tangled when turning the handle. This spindle is specially designed for clamping groups of work-pieces, as well as work-pieces with rough surfaces or very long work-pieces clamped by several vices. Its exterior programmable supply makes it very useful when automating machining systems.