Microlab HR-26E DC Block is used to prevent the flow of direct current and low frequency current surges along the inner conductor of a coaxial cable, while permitting the unimpeded flow of RF signals. Applications include the blocking of current surges in subway tunnels and antenna sites during lightning storms. The ultra wide frequency range allows use in LTE-LAA deployments with multiband antennas. The unit consists of a length of coaxial line with a series capacitor in the center conductor to block the flow of DC and low frequencies, while passing RF with negligible loss or reflections.