Tap question

[keithbyrd]

I want to start playing a bit with kitless pens. So a basic question:
I have two triple start taps both M13x0.80 6H HS. One is marked with a GD-4 and the other GD 5- What is the significance of the GD 4 or GD 5?

 

[edstreet]

Tolerance of precision they are made to.

 

[keithbyrd]

Thank you Ed. Now the next question(s). Is there any significant difference between a 4 & 5? Is the 4 more precise than the 5?

 

[edstreet]

This may help you. Short answer is 0.013mm difference. In all practical purposes there is no difference as both will do the job nicely.

 

[keithbyrd]

Thank you Ed - I appreciate the additional info!