Edwards EST SIGI-271 Intelligent Call PointSIGI 271 Fire Alarm Call Points are part of Edwardss Signature Series system. These integrated assemblies feature the familiar KAC Installers Series Call Point packaged with Signature Series intelligent addressable analogue interface electronics. In all 271 Series Call Points, the switch is held off by the edge of the glass. When the glass is broken by pressing directly on it, the switch is released and an alarm sent to the Signature loop controller.