A removable hydraulic set packer has a piston activated by fluid in the bore of the packer’s mandrel. The memory device according to the present invention includes: a nonvolatile memory; a buffer memory having a higher access speed than the nonvolatile memory; and a control circuit. Unless the \u02dcpresence of the master device in the vicinity of a slave device is verified, the slave device automatically locks itself, switches itself or some import function off or enters a login state. A one-way clutch is connected between a cover of the hub and the planetary gear system so that the hub is rotated when the planetary gear system is activated by the motor. A voice call destination number is identified. The first and second media presentations include substantially similar media content.