Use In: Rotary hammer with Spline chuckSize Range : 3/8" x 8" to 2" x 23"Designed for use in a rotary hammer equipped with a spline type chuck. The bits are manufactured to comform with ANSI Standard B212.15 and can be used to drill in concrete, block, brick, and soft stone. Both 4-X Cutter and single tip head style are available.