High voltage transients caused by lightning strikes have the ability to easily destroy semiconductor junctions, and thus, cause equipment failure and loss. A lightning strike close to data lines can also cause induced currents in lines that can also do serious damage. The AL-D4W-DT high performance lightning protector provides superior protection of DSL and Telephone lines from these transients or surges.The low capacitance diode array minimizes degradation of the DSL signal. This is in comparison to protectors based on high capacitance TVS diodes or Varistors. The high speed diode array responds to transients that are too fast for Gas Tube based protectors to catch. In addition, the design utilizes Thyristor diode technology which has superior power handling capability compared to TVS or Zener diode based designs. The unit will protect up to 4 signal pairs. For more complete protection, two units should be used, one on each end of the line.The compact weather resistant housing features a lockable hinged cover and break-away holes are provided on the rear of the enclosure for mounting. The cable grommet may be adjusted to cable size and is removable.This protector is also available with punch down terminal blocks, AL-D4W-DP.