This cable has RJ45 end connectors and is used to connect the Wakespeed regulator to the Victron Cerbo GX. The length is 4 ft. It is a Cat 6 crossover cable and is different than the standard Victron RJ45 cables which are not compatible with this application. The Blue end plugs into Victron, and the Red end plugs into Wakespeed. (the photo shows two black ends but in reality one end is blue)