Tungsten carbide cutting edges, suitable for DIY & Professional use. The bearing guide pin can follow complex & intricate shapes & the cutters are suitable for use on softwoods, hardwoods, MDF & plywood. Supplied with two bearings 9.5 mm. 12.7 mm. to enable use as either ovolo or rounding over bits. Diameter: 6.5 mm. Radius 6.3 mm. Depth 13 mm. 2 x Bearings supplied 9.5 x 12.7 mm. Shank 1/4 in.