CNC machined Cr-Mo 5/64" single speed sprocket with broad 7mm base.HG type spline compatible.Broad 7mm base avoids the sprocket ripping into Cassette bodies.  Chrome Plated finish.12, 13, 14, 15, 16, 17, 18 or 19T*Note: are suitable for narrow 5/64" (9 speed) chains.