Abstract: A tool to stop the flow of water through an activated fire protection sprinkler head. This tool is designed to be a heavy duty, simple to operate mechanism capable of deactivating fire preventing sprinkler heads quickly. By simply turning the outer housing of the tool, by hand or by means of an adjustable extension pole, shut-off levers of this tool will be moved apart within the bracket of the sprinkler head until co-action between the bracket and one of the levers forces the other lever, preferably one bearing a shut-off gasket, against the open water orifice in the sprinkler head, thereby preventing the flow of water through it.