Thanks for the replies,,,to A.H.74, you made me think I'm losing it, lol because I couldn't find it either...then, I went to us.glock.com, got to the .40 selections, then the 27's..slid over to the 27Gen4 and I quote: "the new Glock dual recoil spring assembly substantially increases the life of the system". Whew, I'm not crazy. It seems like borderline marketing ploys.
I guess I won't even ask what the best IWB leather holster is...got cha...thanks.