some do but some models have a non threaded barrel for sale in restricted states so you need to check the specific model you ar interested in

There are different options on the guns, Just look and make sure the options you want are in the package you are looking at. Most do have threads at the end cause they have some form of flash hinder

Jason, yes Sir, 16 inch barrel with Barrel Twist of 1 in 9" and muzzle threaded the AR Standard /2 x 28 thread pitch.

Jason, Yes. 1/2 x 28 thread pitch for any muzzle devices.