Abstract: A jack consists of a body of the jack (2) sliding on a fixed piston (9) mounted on a support (6) by means of a piston rod (4), and at least one element for guiding the body on the support. The body of the jack is an extruded section (2) containing at least one longitudinal bore (3) used as the piston chamber for the jack, and equipped with at least two guide rods (5) mounted on the section (2) in the longitudinal direction. Bearings (15) adapted to the shape of the guide rods (5) are mourned on the fixed support (6). At least one of the bearings is adjustable. Advantageously, the extruded section (2) is equipped with two hydraulic shock absorbers intended to contact limit stops (21). Limit stops (21) have adjustable positions, and can be retracted and fixed on an L-shaped groove (20) of the fixed support (6).