?️ Standard #countersink #bits are the most commonly used type. This type of countersink #bit uses a conical tip that cuts a chamfer around the top of a pre-drilled hole. These bits are typically used for creating a recess for flat-head #screws.? https://www.reasonsto.com.au/countersink-bit-the-different-types-and-selecting-the-right-one-for-your-application/