a corresponding number of inlets and outlets as in the last example the thread contact means may be arranged in such a manner that they intersect the channels 16 17 in a part of the annulus 20 further the sleeve may be moved to a section of the annulus 20 having an even annulus surface 18 where it consequently will be a smaller restriction of the flow this embodiment having channels 16 17 that do not intersect each other may advantageously have used when it is desirable to have less restriction of the inflow when the inflow regulation device is in its fully open position than the restriction sustained by the device in the foregoing example the restriction in the fully open position may be further decreased by giving the annulus surface 18 a shape such that it forms a space or clearance 28 fig4 between the sleeve and the annulus surface 18 at the section fig6 shows an embodiment in which an inflow regulation device may be operated by a hydraulic double acting ring piston device 25 26 having connectors for fluid 28 29 as shown in the figure a sleeve 1 may be connected to a ring piston 25 for axial movement the ring piston may.