Serious engine builders and backyard mechanics alike need these special length brushes to properly clean all the holes and passages found in most automotive engines. Available in a wide variety of diameters and lengths, each brush is made from pure stiff bristle nylon that won't soften or melt when used in conjunction with most engine cleaning solvents. To minimize bending, each handle is made from heavy gauge twisted steel wire, which also firmly holds the bristles in a spiral twist. A convenient loop on the end of each brush makes for easy hanging and storage. Deluxe Brush Kit - includes one 5/16 inch, 1/2 inch and 5/8 inch o.d. (outer diameter) x 9 inch and one 1/2 inch, 5/8 inch and 3/4 inch o.d. (outer diameter)x 25 inch overall length brushes.