This 4mm DDS tape cartridge is 125 meters long and stores 12GB of uncompressed data and 24GB of compressed data. Sony's DDS (Digital Data Storage) cartridges last up to 1,000 write/rewrite cycles, feature a heat resistant shell that withstands high temperature, a anti-static shell that attracts less dust and helps maintain low error rates, and internal components that are designed to reduce torque and provide better drive compatability. They come in tough polypropylene storage cases.