Computer Equipment Surge Protector (610-2122) Hints and Tips Faxback Doc. # 32766 This Surge Protector has single telephone line protection (for Line 1 only). Line 2 is passed through and not protected. The 610-2122 is neither a Sine-Wave Tracking nor an Envelope Clamping device. It is an avalanche device ( MOV) which simply clamps at the rated voltage. The unit meets IEEE 587, which has been superseded by ANSI C62.41-1991 and which the unit also meets. (IR-05/15/96)