? Simplifies periodic flipping of the wheels for maximum cutting, long life, and safer use ? Featuring a knot twist with the most aggressive cutting action, the new dual-hex nut makes it easier for the user to regularly switch mounting position and keep the brush running at peak performance. ? Highest quality heat-treated steel wire and construction that delivers smooth operation and long life. ? Hex nut design provides adequate tool clearance ? No need to remove the guard from the right-angle grinder