I'm no expert, but mine starts with HK and it operates just fine.
From what I have read, the one you are looking at is newer than mine.
Should be good to go, try the search tool.

 

If you call KT and tell them the number they'll tell you when it was made.

 

I just found this, hope it helps.

http://www.ktog.org/cgi-bin/yabb2/YaBB.pl?num=1143766924/0#0

 

the above link would also be the 4th hyperlink in the FAQ & VIP sticky

 

Thanks for the4 link. I didn't find anything that helps me determine if the gun is new eough to be past the early problems, etc. How do I determine what Gen it is etc?

 

Thanks for the4 link. I didn't find anything that helps me determine if the gun is new eough to be past the early problems, etc. How do I determine what Gen it is etc?

What were the early problems?

Here is a post where the same question was asked.
http://www.ktog.org/cgi-bin/yabb2/YaBB.pl?num=1244771992
the quick answer, there is no S#s to avoid (except possible the thin guide rod hole slides if you don't want to speend $0.25 to fix)

 

I thought gen I guns had some issues?

 

HWMXX would be a 2G

you could surmiss from the photo of the 1G and 2G side by side shows H0 and HF

 

This might be what he's thinking, mine is a HK 2G one, and has the older hammer block.
Keltec sent me the new one free. That's the only new part for the early 2G ones, per Keltec.

 

the new hammer block would be post JRWXX (5/2008)