A mixer drill is a tool that is used for mixing different types of material , both mud type and liquid type. Usually a good mixing drill should be equipped with a few features for the process of mixing to be efficient and effective. These features include having a low rpm range especially for mixing materials like mortars, a good deal of torque , variable speed, and off course choosing a brand that is reliable. Mixer drills are good for mixing mud type of materials like cement , small batches of concrete and mortar. Also some mixer drills that are equipped with a variable speed control trigger that makes the tool operates much better when you mix more liquid type materials like as grouts , paints, etc.