Kawakita Denki Kigyosha (Japanese for "Kawakita Electric Company"; commonly known as KDK), is the brand name used by Matsushita Ecology Systems Co., to manufacture the group's ventilating products. Before becoming part of Matsushita Electric, KDK was a separate company not affiliated with Matsushita Electric Industrial Co. Ltd. KDK was registered as a trademark in 1912 but originated in 1909 as Nippon Electric Industry Co. Ltd.