Abstract: The regulator and shut off valve for a corrosive media, particularly for a wet chlorine-containing gas and a chloride ion containing fluid, comprises a pressure resistant housing and a shut-off member held between at least two seat rings. The housing has a passage for the corrosive media. The seat rings are supported in the housing and contact the shut off member under tension. To protect against abrasion and erosion the housing is made of titanium or a titanium alloy, at least one sintered ceramic wear sleeve is provided on the circumference of the passage in the housing and the wear sleeves are inserted in the housing with radial play an with axial play so that a space is formed between the outer circumference of the wear sleeve and the housing, which is connected with the passage cross section of the wear sleeve by a compensating gap.