Yes, these will function in a 39-2 but they are not the original style magazine. They extend a little beyond the grip. I personally do not like them in my 39-2 or 639.

I believe it was a Pro Mag magazine that BrianE was inquiring about. Normally I do not care for Pro Mag magazines but the Pro Mag magazine for the 39 does function and fits better than even the S&W magazines referenced above. The only fault I have is that the base plate is longer than the original S&W.