Abstract: An apparatus and method for isolating a portion of a well bore and providing pressurized fluid thereto includes an upper packer, a lower packer, and a sliding sleeve between them. A seat is defined at the open bottom end of the lower sleeve and a sealing element is configured to seal the seat. A bias force urges the sliding sleeve toward a closed position. The apparatus moves along the bore and the lower packer is set at a desired location, and then an opening force is exerted on the tubing to move the sliding sleeve to the open position. After the lower packer is set and the sliding sleeve is open, the upper packer is set to isolate a portion of the well bore between the packers with the sliding sleeve in the open position to provide a flow path from the tubing string to the formation between the packers.