First time post, pleasure to be here. I am in the process of buying a used PT145, duotone black frame-stainless slide. I am having trouble identifying what generation it is. I have read so much but am still confused. It appears to have features of 1st and 2nd generation. The serial number only appears on a metal plate at rear of the gun (NUH *****). This indicates it was produced in July 2001. I could not find the SN on the slide anywhere. It has the TSS security system (2nd Gen?). There is only Millenium on it, not Pro (1st Gen). It has a textured grip (2nd Gen?). I am not sure what action the tirgger is. I have not shot it. When I dry fire it there ss a difference from my Glock 19. When I dry fire my Glock I have to rack the slide between every shot. With the PT 145 I only have to rack the slide once and it keeps firing without having to rerack the slide. I am somewhat inexperienced so I don't know if that makes a difference. I was thinking that possibly the frame was replaced on the original slide 9maybe due to crakcing). Is that possible? Based on this info can anybody help me identify the generation of the pistol? I can post photos once I acquire the gun. Can anybody post photos of both sides of multiple genreations to compare? When did 2nd begin production? When did upgrades to 1st gen begin? Also, if I provide Taurus with the SN can they identify it or give me a history on the gun? Thanks.