The MS-012 packaged Fixed Voltage Single Port Series are SIDACtor® devices designed to protect sensitive SLICs (Subscriber Line Interface Circuit) from damaging overvoltage transients. The series provides single port protection using a fixed voltage switching device for negative surges. Positive surges are routed though internal diodes to a ground reference. The series is also pin-to-pin compatible to industry standard programmable SO-8 SLIC protectors.Applicable Global Standards TIA-968-A ITU K.20/21 Enhanced Level ITU K.20/21 Basic Level GR 1089 Inter-building* GR 1089 Intra-building* IEC 61000-4-5 YD/T 1082 YD/T 993 YD/T 950 *Series resistance required.