The yellow tubing brings fresh air aboard Texas, so that her two open hatches don't become wind tunnels as her own ventilation blowers suck in air. The black, snake-like cables bring shore-power aboard (we got by with two, each about one-third the size of these. But then we didn't have to power up a nuclear reactor to get underway, either.) The big, black inner-tube looking things are meant to keep small craft at bay. (There is a *lot* of no-so-obvious security present,but probably not enough to ward off determined professionals.)