Precise channel cutting in brick! Concave design for accurate channel cutting. When installing pipes or cables in a wall, you need to chisel clean, precise channels. The PRO SDS max Hollow Gouging Chisel is a reliable and precise accessory we developed for this purpose. We designed the PRO SDS max chisel for electricians, plumbers, and HVAC technicians who need to cut clean channels in brick and concrete walls. The chisel's concave design allows for precise and easy channel cutting. You can use the chisel with your SDS plus hammer.