Where the C3 Pro had the Bluetooth antenna built-in, the C4 takes it a step further and integrates the mic, speakers, and antenna. As a result, the C4 is already 2/3 of the way there when looking at in-helmet audio/communications… all it needs is the SENA SC1 (sold separately) to...
pre-installed in the helmet between the hard shell and the EPS. There are actually two antennae, a small one for Bluetooth and a long one (31 inches) for FM radio. Any ham radio operator will tell you that an antenna becomes efficient when its length increases to about...