The invention is directed to a gas cylinder valve (2) comprising a body (4) with an inlet (18), an outlet (40) and a passage (20) fluidly interconnecting said inlet and outlet; a shut-off device (22) with a seat (26) formed in the passage (20) and a shutter (24) movable along a longitudinal axis (7) for cooperating with said seat; a spindle (12) rotatably mounted on the body (4) along the longitudinal axis (7) and cooperating with the shutter (24) such as to move said shutter upon rotation of said spindle; a residual pressure device (28) fluidly downstream of the shut-off device (22), with a seat (32) formed in the passage (20) and a piston (30) movable along a transversal axis (38. At least one of the shutter (24) and the piston (30) shows a recess or opening (24.4) accommodating the other of said shutter and piston.