In our opinion, the large open faced dive knife (aka diver's tool, aka B.F.K.) is nearly useless underwater, more likely an entanglement hazard than a solution. Although they might have their place on deck and in commercial diving, we don't know any experienced sport or technical diver who carries a large knife strapped to their leg, so Dive Gear Express doesn't sell them. The large cutting face and point also make the typical dive knife generally unsuitable for a precise response to an emergency situation. Because the Trilobite line cutter is a two-sided cutting tool, we've heard divers express concerns they might inadvertently cut something with the other side. Frankly, it's a really bad idea to start waving any cutting tool around and recklessly hacking away at stuff, regardless of the design. Slow and deliberate movements are the appropriate way to use all cutting tools. As for the clever two-sided design of the Trilobite, by holding it with the index finger over the unused side, the Trilobite automatically becomes one-sided.