Double / Dual Layer is a recordable disc providing 8.5GB capacity on a single side (2.6GB for 8cm discs). Compliant with the +RW Alliance (Double Layer) or DVD-Forum (Dual Layer) specifications.
The double / dual layer of recording has been made possible by the creation of a new substrate layer that sits in between each recording layer. This allows the laser beam to record on both layers. Once the first layer has been recorded, the laser re-focused to record on the second layer.