proof mark meaning

[benjf1]

Good morning,
I have a question about what some markings mean on my new (2015 issue) CZ75B compact, searched here for an answer but came up empty. The letters CIP over the letter N are stamped on the barrel, slide and frame. This marking is stamped just in front of the serial number starting with B. Just curious what this means.
Thanks  for any info,
Ben

[QBToo]

I have proof marks from 2 different proof houses.  Here's a link about the CIP designation http://www.mdwguns.com/CIP.html

I forget what they say the N stands for...(ahhhhhhh.......see below post by Wahoo)

Here are my 2 proof marks

[benjf1]

Thanks a lot QB! I searched the term C.I.P. also, but never would have figured that out. I appreciate the knowledgeable help that's available on this site. I'm getting an ammo order of different brands and grs. today and hope to get to shoot soon to see what it likes best.
Thanks again,
Ben

[Wahoo1 again]

The "N" stands for Nitro, it's an older standard from the early days of smokeless (Nitro Cellulose)  powders.