As far as I know, both generations of FS2K trigger packs are white. Now, I do believe the full auto pack it black.
I have a Gen 2 and it looks like yours, minus the auto/safety (whatever it's called) sear that FN omitted in the Gen 2 packs. Is there a reason you think that it's not a Gen 1 pack? It appears to be, but I'm not an authority.
Its a Gen 1 FS2K Hammer Pack. The F2K hammer pack is a different color and slightly different design. Even so, this hammer pack is quite easily modified so that you can go to jail if you choose to do so. People will pay a premium for this Hammer Pack just because of the above.