DP. and PT. Definitions

I can get you halfway there. "DP" means "deep." Apparently 10.2 mm drill is the correct size for tapping M12x1.75 metric threads. But I haven't learned or figured out "PT" yet. (It might mean "partially threaded", since you are not threading to the bottom of the hole.)

I'll take a guess that PT is point as in drill point.

tks dude ,PT stands for point in this context

Hmm... I saw your problems and
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This is a metric way of dimensioning a hole. We in the U.S. measure a hole to the rounded end of the drill not to the end point of the drill.

In this case, the engineer wants to drill and tap 4 holes.

He wants to use a 10.2 mm dia drill and an (M12) 1.75 dia tap drill.

The 4 holes are 10.2mm (Dia) X 32mm deep to the end point of the drill and

tap the 4 holes to (M12) 1.75 X 22.2mm deep.