Glyph GPT50 GPT3-4000 4TB USB 3.0 External Hard Drive "Choose from 500GB, 1TB, 2TB, 3TB, and 4TB capacities Rotational speed of 7200 RPM Optimized USB 3.0, FireWire, and eSATA connectivity Intelligent temperature-controlled quiet fan Industry-standard power cord and a pro-quality internal power supply Disk health monitoring, drive analysis that never sleeps" Rotational speed of 72 RPM "Optimized USB 3., FireWire, and eSATA connectivity" Intelligent temperature-controlled quiet fan Industry-standard power cord and a pro-quality internal power supply