HPE magneto-optical rewritable cartridges allow virtually unlimited read/write cycles, making them the ideal choice for data management in information-intensive environments. HPE write-once cartridges are designed for permanent storage of data that can't be altered or erased. Both disk formats have an archival life of 100 years & are engineered to HPE's exacting quality standards. Select HPE optical disks to enhance the reliability, performance, & longevity of your drive. Each HPE optical disk is encased in a sturdy, poly-carbonate casing to inhibit both the attraction of dust particles & static build up.