This high performance 3-stage lightning protector provides superior protection for Telephone and DSL lines. Shared phone lines carry the ring voltage for standard telephones. The unit protects against both differential and common mode transients.The first stage is comprised of a differential gas discharge tube. Stage two is a pair of current limiting series resistors and the final stage is a low capacitance diode array. The use of three terminal differential gas discharge tubes provides superior protection against surges. The second stage series resistance limits the power dissipation of the fast diode clamp array in the third stage. This allows time for the slower but higher power gas tubes to flash over. The diode array clamps the leading edge of fast transients to safe levels until the high power gas tubes turn on. This eliminates the damaging leading edge spike that single stage gas tube protectors let leak through. The 3-stage design can handle higher-level transients than a protector that uses only diodes.This protector features an industrial grade die cast aluminum enclosure with gasketed cover and concealed mounting holes. It includes an aluminum mounting kit and hardware. PG16 cable glands are provided on the enclosure as well as an external ground clamp to provide a tie point for earth ground.For mounting to masts up to 2 inches in diameter, the HGX-PMT24 mast mounting kit is available (sold separately).For addtional information and complete specifications, see the data sheet below.