9pcs Air Hammer Punch Chipping Bits Tool Features: 9 kinds of different shape Air Hammer Chisel, provided the needs of different jobs. Correctly hardened and tempered so blade will not shatter when struck hard. Manufactured with Heat treated high carbon steel for necessary hardness and durability. 0.39 inches Round Style shank chisels for heavy duty service work. Application: Fits most pneumatic hand held air impact hammer, scrapper or chiseler. For masonry and concrete demolition, light chipping and chiseling of tile, mortar, glazing compounds, and other masonry products.