This read-write counter controls how long, in tenths of a second, this specific physical drive's LED continues to blink, with zero meaning it is not blinking and 4,294,967,295 returned if the value cannot be determined or the drive isn't in a hot-plug tray. An admin writes a time value here to make a single target drive's LED flash so a technician can find the exact bay to service, distinct from the logical-drive-wide blink control. For example, setting this to 600 makes just this one physical drive blink for one minute, helping a technician distinguish it from its neighbors in a dense enclosure.