That's actually closer to an LS than a standard 3913; The 3913 has an ambi safety/decocker, and the frame has a different taper to it under the barrel. I'm color-blind, but the LS is also a little bit different in color, and came with Gray grips originally. Same as the black ones on the standard 3913. It would help to see the left side of that, but I know of what I speak.(I have 5, a few 3913's, a 3913LS, and a 3913TSW. All minor details by the way, the 3rd gens are all great. If I add in the 5906's (2), the 4013's (3), and the 4013TSW, I have 11 altogether. SO FAR......

Congrats on your purchase, you won't be dissapointed!
Good luck, Dave