Designed specifically for homes with alarm systems, the Z-A431PJ31X-A alarm filter keeps DSL service, home phoneline networking (HPN) and alarm systems functioning as they should. The alarm filter blocks DSL and HPN signals from interfering with the alarm system's voice-band modem. At the same time, it isolates DSL and HPN equipment from alarm equipment impedances. With this two-way protection, the alarm filter keeps the alarm system operating reliably around the clock and ensures fast, uninterrupted DSL and HPN access even while the alarm system is dialing. Installation is a snap for the service technician -just plug the filter into the alarm panel’s telephone connection (RJ31X-RJ38X). The alarm filter's premium performance and reliability means fewer service calls for providers, more satisfied customers, and cost savings for everyone. Key Features Filters one alarm panel telephone connection (RJ31X-RJ38X) Compatible with all major home alarm systems Reliable, uninterrupted DSL/HPN and alarm operation Supports G.lite, G.dmt, ADSL, V.90, Caller ID and metallic-loop testing Compliant and listed with UL and CSA Compact in-line design - plugs into any standard phone jack Supports alarm panel line-seizure and cut-line protection features