KEO 53519 Cobalt Steel Single-End Countersink Set, Uncoated (Bright) Finish, 82 Degree Point Angle, 5/16" - 1" Head Diameter

If the shanks had three flats ground on them like some of the better quality drill bits, they would be real winners.

These countersinks are the best I have ever used. I am a machinist and so I use these every day. From chamfering a hole to countersinking for a flat head bolt, these do the trick with no chatter or burrs. You do have to be careful if you are chamfering a diameter with a very heavy burr on it free hand (like plastic loves to do), you will probably end up with a lopsided chamfer. This is not the tools fault, but your own.For the professional tradesman...these are the way to go, I have tried more inexpensive styles and was greatly disapointed...break with the bucks and buy the best .

I was way more impressed with these that I would have predicted. I use them for wood working and they bore clean and precise countersunk holes (using a drill press - have not tried them with a hand drill). They produce a smoother cut and extract the debris significantly better than traditional countersink bores.

Items delivered in the time promisedCounter-sink bits are high quality steel and machiningWill probably last a life time when used on woodsCut cleanlyBarely noticeable run-out is likely caused by my drill chuckCan be used with soft metalsComes in sturdy plastic caseWould definitely purchase again

Really nice set of chamfer bits, I get no chatter marks from these as opposed to regular fluted chamfer bits. Very nice quality

Comes in a nice plastic case and they are very high quality.

Good quality, excellent cut finish.