The DAK-2S dual master adaptor kit is designed for use with Aiphones C-123L and LEM series. The kit contains component modules to allow two master stations to answer a single door. Additional kits may be used to add more than two masters to a system. There is no master-to-master communication, and only one master may be used at a time. A power supply is required for each master. Datasheet DAK-2S.