Some months ago Kel Tec introduced an extended 9rd magazine for it's .380acp P3AT pistol. Well, guess what else it fits...
Mine just came in the mail last night (after being back ordered for months), and with a few o-rings installed in the gap between the grip and the grip extension, it fits very snugly and offers a huge improvement in obtainable grip. Plus, it turns the LCP into a 9+1rd capacity pistol, vs the factory stock 6+1 capacity.
Have yet to testfire it at the range, but it seems to work fine.