RE-2AS 4L and RE-2AS XL products series are expansion modules created for RE-2AS Systems, to add an extra communication port. That makes possible the RE-2AS nterconection, performing an united system up to 60 zones. The RE-2AS-4L module provides redundant communication so that the system is monitored and can be controlled according to EN54 requirements. There are two available models that allow systems consisting of up to 4 units and 24 zones with the RE-2AS 4L model or up to 10 units and 60 zones with the RE-2AS XL model.