Matsushita Electric Industrial Co and its Matsushita Communications Industrial Co affiliate are putting into production a 5.25 optical disk drive and medium – erasable, presumably – developed by Nippon Telegraph & Telephone Corp: the exchangeable disks, which use a Terbium and Iron medium, store 600Mb, and NTT has also developed an auto-load feature that can mount and demount up to 24 disks; the drives will cost about $4,000 and the auto-load library system around $24,000.