The BC Series Flex-Hone tool is designed for use on any type or size of cylinder from 4 mm up to 3 in. diameter. Designed for surface finishing and cross hole deburring in brake cylinders wheel cylinders hydraulics pneumatics and valve guides.Features. A resilient flexible honing tool with a soft cutting action.. The abrasive globules each have independent suspension that assures the Flex-Honer to be self-centering self-aligning to the bore and self-compensating for wear.. Item Weight - 0.100 lbs.