Pocket Knife versions of Dive Knives are rare, but the market does offer a selection of practical knives popular as backup. In an emergency under water, e.g. if a diver gets caught in an old fishing net, being able to cut through the net quickly and effectively is essential for survival. Therefore, many diving knives have blades mainly designed for cutting though netting and lines. Of course, these knives are also highly corrosion-resistant. However, proper knife care, especially after use in salt water, is a must.