Designed to meet the reliability, endurance, and performance requirements of 24/7 storage in small- and medium-sized business storage systems, the 12TB HAT3310 Plus Series SATA III 3.5" Internal NAS HDD from Synology delivers NAS-class reliability to ensure consistent performance in high-uptime and multi-user environments. The HAT3310 Plus has passed 500,000 hours of testing, has a Mean Time Between Failure (MTBF) rating of 1.2 million hours, a yearly workload rating of 180TB, and is filled with helium instead of regular air. Also featured is a storage capacity of 12TB, a SATA III 6 Gb/s interface, a 512MB cache, and a rotational speed of 7200 rpm, all of which help to ensure uninterrupted data transfers with sustained speeds of up to 281 MB/s.