One of the great things about Air Tools is how quickly you can change from one tool to the next. That ease of use comes from the use of a Quick Coupler. There three major types of fittings Milton (the most common for home owners), Industrial Interchange Coupler, & Automotive Standard. So make sure you have the right one, and working with your air tools will be a breeze. Tool King has all of the Couplers you need at some amazing blowout prices.