The Schneider Electric Acti 9 iPRF1 3P 12.5R is a Type 1 (Class I) Surge Protective Device from the iPRF1 series, featuring a 3-pole configuration and a built-in thermal disconnector ("R" version). It is designed to provide primary protection at the service entrance of three-phase electrical systems against direct and partial direct lightning strikes (10/350µs waveform).