The MARSILI hydraulic cylinders combine and accurate machining to an highly innovative technology to assure maximum performances and a high resistance to corrosion. The hydraulic actuators of this series are made up of two cylinders: a main force cylinder and a feedback cylinder coupled to the main one with an aluminium support. The cylinder tube is made of brass, a material which has higher resistance to pressure than aluminium. Double seals are inserted on each cylinder head to compensate the micro leaks which occur after many working hours. To facilitate the bleeding of air, inclined bleed screws are installed on top of the cylinder heads. The piston rod is made of stainless steel, chromed and rectified; the chromium plating in a protected environment guaranties a high quality plating, and an excellent protection against the marine corrosion, combined with a very smooth surface guaranties a long endurance of the seals. The chromium helps to eliminate at least 30% of the friction caused by the use of seals and its hardness protects the piston rod from accidental scratches which could damage the seals. The support is made of brass and bronze. All MARSILI cylinders are certified CE and are approved by the most important international classification societies.