The 9 round magazine for the Kel Tec P3AT 2nd Generation. Materials Required: 1 standard P3AT Magazine. 1 North American Arms Magazine with round Extender. Item # MZ-380_EXT $30.00 from NAA http://www.naaminis.com/guardacc.html#parts 1) UNLOAD THE GUN! 2) REMOVE ALL ROUNDS FROM ALL MAGAZINES! 3) Completely dissemble both magazines. Remove the base of the NAA extension like most magazine bases to allow removal of the spring and the follower. Removal of the extension from the NAA magazine requires that the back plate come off first. Fit a small screw driver or something into the hole in the back of the extension and push/pull it down. The dovetailed piece slides down, then the extension can be removed from the NAA magazine. 4) Slip the NAA extended base onto the bottom of the KT magazine. 5) Slip the NAA follower and NAA spring into the now extended KT magazine body. 6) Assemble the NAA magazine extension onto the KT magazine. Gently slip the converted magazine into the 3AT. You will notice that the magazine does not seat well. The problem is that the KT hammer spring catch (part # 279) does not conform to the top of the NAA extension base. Simply stuff a rag down the 3AT grip magazine well, and sand down the hammer spring catch. There is ample material on the catch to still retain the hammer spring pin (part #274). Use caution at this step to not over do it. It should be a sand a little, fit…sand a little more, fit type process. You can use a Dremel sanding drum on it, but remember.. go slow and easy. It does not take much to get a nice fit. You could take the hammer spring on and off during this step if you are worried about marking up your grip, but then you run the risk of stretching the hammer spring, not to mention the hassle of taking everything apart many times. 10 rounds can go into the magazine at this point, but to much pressure is on the rounds to pop into the KT magazine catch. I have not tried it, but it may be possible to clip a loop or two of the NAA magazine spring to allow for round ten. I went to the range with all of this done. I only shot one magazine full but no failures of any kind with this set up. Any questions, comments or tips are welcome.