The AS-5 Packer is a compression set tool with a J-slot to control pack-off. It is run above other packers - such as the AS-III Packer - to selectively treat, produce or inject in multiple zone completions. It is also used to isolate casing hole perforations. This packer features a large by-pass area to prevent swabbing when running and retrieving. When releasing, the valve allows debris to be washed from the upper slips.