Package: 1 of 4” 102 mm carbide hole saw drill bit. Cut Abrasive Material： The carbide grit hole saw cuts through a wide range of abrasive materials. It compares with Bi-metal hole saw cutting the abrasive material, up to 3X longer life. Max Cutting depth: Up to 1-1/2” (38 mm) More Hard Teeth: The carbide grit teeth hardness over 80 HRC. It is more sharp, hard. Application: It’s fit for recessed lighting, dryer vent hole and other roof vent. It is for Air Brick, Fiber Cement Siding, Backer Board, Stucco, Plasterboard, MDF, Hardy Plank, cement board, sheetrock (no good for wood). This carbide grit hole saw bit is for Air Brick, Fiber Cement Siding, Backer Board, Stucco, Plasterboard, MDF, Hardy Plank, cement board, sheetrock.