Send up to 1 Amp DC and up to 50 Volts DC down a coax cable to power equipment (automatic antenna tuner, relay box, etc.) without running a separate power cable. Requires one MFJ-4116 on each end of coax cable to inject DC power and to retrieve DC power. 1-60 MHz. SO-239 connectors. DC jack. 2¾W x 2½H x 1¼D inches.