Abstract: A device and a method for selective control of fluid flow between a flow pipe (14) of a well and surrounding rocks (12). The flow pipe (14) is provided with at least one flow-through particle filter (16) placed externally on the flow pipe (14) and between the flow pipe (14) and the rocks (12). The filter (16) is connected in a flow-through manner to the flow pipe (14) via a flow channel (38). The characteristic of the invention is that the flow pipe (14) is provided with an imperforated pipe wall inside of and vis-a-vis said flow channel (38) when installing the flow pipe (14) in the well. Then the flow pipe (14) may be perforated selectively inside of the flow channel (38) for one or several filters (16) along the flow pipe (14), whereupon fluids may flow through the flow channel (38) and the filter (16) via perforation apertures (54) in the flow pipe (14).