The Mechdynamic Picatinny Rail Groove Female Form Tool is designed to do CNC machining of groove geometry that matching the standard Picatinny Rail. This 3 flute form tool allows an excellent chip load per tooth while maintaining high rigidity and designed be used to finish the Picatinny Rail groove inside contour. Without this tool/cutter, you will need to use a combination of tools which takes multiple tool holders and prolonged tool running time not mentioning the tolerance introduced on each tool change. With this tool in hand, all that problems mentioned above will go away. All you will have to do is to rough the stock and finish off the final contour. This tool/cutter is a must have for any shops that are looking to cut the Picatinny rail grooves accurately and cost-effectively.