Abstract: A shock absorber is made with a bleed function and preferably a non-return valve function associated with the bleed function. The shock absorber has a cylinder (3) and, working in the latter in working medium and arranged on a piston rod (4), a piston arrangement. The latter comprises at least two first and second pistons (5, 6) arranged at a distance from one another on the piston rod. At least one piston (5) can, in connection with an end position, be introduced into a first space so as, depending on its position in or at the space, to bring about a modified or varied damping force relative to when the piston is located outside the space. The piston rod (4) is provided with an inner second space (15) which is arranged so as to contain said bleed and/or non-return valve function. Additionally or alternatively, the piston (6) working outside the first space is provided with a member performing a bleed function and with any associated non-return valve function.