Tandy Corp has not revealed what technology it has developed for its Thor-CD erasable Compact Disks, but consultant BIS Mackintosh reckons that it is a variation of dye polymer, where a high temperature laser creates pits in the surface to record, and longer exposure to a lower power laser is used to cause the deformed surface to return to its original state and erase the recording – cheaper than either the magneto-optic or phase change record-erase technologies: BIS Mackintosh highlights the fact that Tandy has admitted it doesn’t yet know how many recordings and erasings a disk will stand, raising questions about its use as a data storage medium.