Chromatography column comprising a column tube and at least one adjustable adapter assembly with a plunger that may be positioned at a plurality of longitudinal positions in the column tube, wherein the piston is arranged at the end of a threaded piston rod arranged with the threads engaged by a rotable end cap for enabling longitudinal movement of the piston by turning the end cap, and wherein the adaptor assembly comprises rotation prevention means arranged to prevent rotation of the plunger rod in response to turning of the end cap.