Precise channel cutting in bricks. 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 designed for this purpose. We developed the PRO SDS max chisel for electricians, plumbers, and sanitary installers 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.