Addicted2Fish premium surgical grade stainless steel Crescent Moon Cutters are primarily designed for use in marine aquariums for trimming corals and producing frags.  The blades are of surgical quality and are able to cut through thick coral with ease.  The cutters can also be used in freshwater terrariums to cut through thick growth.  To ensure longevity, please rinse the tools in freshwater and dry thoroughly after each use.