Check the listing for details. CO2 and Nitrogen Tank Wrench - Metal. Condition: New. Listed at 12.99 USD. Tired of scratching up your regulator or having to go find a tool to remove the tank? This wrench is the perfect tool for you! Its simple design makes it easy to screw on and off your tanks. The handy thing is that the tool stays on the regulator so when your ready to use it again no need to go find it!