I purchase this firearm recently and intended on installing a Flash Hider but when I tried to remove the threaded cap on the end of the barrel it wouldn't give, so I headed up to my local gun shop and they were unable to remove this cap. Seems like this cap was welded into place. I have contacted the seller and kel tec and waiting for a response, any member here have an issue like this, I'm quite pleased with the firearm other than the way they installed that F****** cap.