Essential Tool for AN Fittings: The Speedway 37 Degree AN Flare Tubing Standard Tube Flaring Tool is specifically designed for creating clean and accurate 37 degree single flares required for AN fittings., Versatile Compatibility: This tool works with various soft metal tubing materials such as aluminum, copper, and mild steel, making it perfect for brake or fuel lines., Wide Range of Tubing Sizes: The flaring tool is compatible with tubing sizes ranging from 3/16″ to 5/8″ OD, including 3/16″, 1/4″, 5/16″, 3/8″, 1/2″, and 5/8″., Easy to Use: With its simple and user-friendly design, this tool ensures easy and hassle-free operation, allowing you to make precise flares every time., Not for Stainless Steel: Please note that this flaring tool is not recommended for use with stainless steel tub.