Tool sets with countersink

Countersink

— the term "sink" most often means a device for creating conical recesses — for example, for screws with a countersunk head (technically, the term "counterborer" is more correct for such a device, but in fact it is rarely used). There are also other types of countersinks — for example, for cylindrical recesses; they are much less common, but anyway, when choosing a set with a countersink in the kit, it's ok to clarify what exactly is meant in a particular case.