Spartan Blades CQB tool. Real world tests on blades are a challenge when that blade has one primary purpose: to push through flesh quickly, again and again. To test the edge as well as the CQB tool’s durability, I took it out commercial fishing in Alaska. For 30 straight days, I used it in an abrasive salt-water environment. I didn’t clean it or even wipe it off. It saw the insides of dozens of sockeye salmon, countless coho and a handful of king salmon. At the end of the season, I washed it off and checked the blade: still exceptionally sharp, having lost little of its edge.