CBi QKL-3(13) Mini Rail Surge Protector with Indication 3P 275V 40kAProduct Features LED indication of the SPD's condition while ON, the SPD is functional, if OFF and the mains power is still available, then the SPD is no longer functional and should be replaces Thermal disconnect device (prevents potential thermal runaway problems) One port SPD (no series impedance) Requires to be backed up by a QF MCB Safety Features Requires to be backed up by a QF MCB Surge Protection Devices should be installed by a trained