I have both the blue and SS flavors of the CS45. It is 45ACP and is, sadly, no longer manufactured. I find it to be a reliable, accurate and easy to conceal weapon that is my daily carry. I use a blade tech IWB holster and no one at my office or elsewhere is ever aware it is there. I load it with Federal EFMJs. If you can find one, give it a try. The only more concealable 45 I have ever found that was reliable (as in bet your life on it) was the Star PD, (also out of production) but it was a 1911 copy so it had to be carried cocked n locked, which always made me nervous. Also, the Star PD was VERY unpleasant to fire, but the CS45 is fun. I can run 100 rounds through it at a session and stil want to shoot more. I carry the CS45 with one in the chamber, safety off, so I don't need to turn the weapon 'on' to use it.