The AL-D8 AC series of high power 3-stage lightning surge protectors provides superior protection of control lines from transients and surges. These units will protect 8 individual single ended AC control lines. The first stage is comprised of a spark gap. The second stage is a failsafe fuse and the final stage is a Metal Oxide Varistor (MOV). The unit limits the positive and negative voltage swing on the line to the Varistor voltage rating. Call for different Fuse and Varistor ratings. Use the AL-D8 DC series if uni-polar voltage swing is required. For more complete surge protection of control lines, the use of two units is recommended, one at each end of the line.These units feature a weatherproof ABS enclosure with gasketed cover and concealed mounting holes. Removable Terminal Strips are provided on the input and output for convenience. To ease installation, the terminal strips can be removed. A ground clamp provides a tie point for earth ground.For mounting to masts up to 2 inches in diameter, the HGX-PMT25 mast mounting kit is available (sold separately).This protector is also available in 12V and 24V versions.