Verbatim M DISC™ optical media is the new standard for digital archival storage. Unlike traditional optical media, which utilize dyes that can break down over time, data stored on an M DISC is engraved on a patented inorganic write layer – it will not fade or deteriorate. This unique engraving process renders these archival grade discs practically impervious to environmental exposure, including light, temperature and humidity.ISO/IEC 16963 standard longevity tests have proven the durability of M DISC technology, and it withstood rigorous testing by the US Department of Defense. Based on ISO/IEC 16963 testing, M DISC media has a projected lifetime of several hundred years.Designed for widely distributed large data such as scientific images, video, and other commercial application object data, Verbatim M DISC BD-R DL media have a storage capacity of 50GB – allowing you to use fewer discs while archiving your files.- Projected lifetime of several hundred years (based on ISO/IEC 16963 testing)- Stored data is engraved – ultimate archival solution- Impervious to environmental exposure, including light, temperature and humidity- Withstood rigorous testing for durability by US Department of Defense- 50GB storage capacity- 10-Year Limited Warranty