A lightning arrestor connects the antenna to the antenna cable. It passes the RF signal from one to the other through a medium that, when it gets too much power, it breaks, just like a fuse. A lightning arrestor will NOT stop a direct lightning strike. All a lightning arrestor really does is protect your electronics against the static electricity that can build up during a storm. About 50% of our customers opt to ground their antennas. A lighting arrestor is not mandatory.Most customers use 10-gauge copper wires to ground their Helium setups.