Point numbers indicate the length of the drill flute which determines the metal thickness that can be drilled.

The flute has a channel for removal during drilling to prevent splitting.

If wood is greater than 1/2" and steel is 18 guage or thicker, specialty winged screws must be used to prevent "jacking action".

Max drilling capacity = length od the unthreaded section from the point tip to the bottom of the first thread.