TRANSTECTOR's I2R-75KS277 277 VAC, one-pole, single-phase, two-wire modular protector. This modular, 20 kA, single-phase surge protection device is engineered for industrial communication applications. Network safety and reliability are built into the I2R 75K series. Engineered using patented safe-fail self-protection design, the I2R surge protective device (SPD) couples a high short circuit rating with thermally protected metal oxide varistor (MOV), which eliminates the need for additional overcurrent protection devices.