Getting back into Autocockers and was looking for this barrel kit. This is designed with Autocockers in mind, with longer backs to stick past the front pneumatics so you have something to grip. I use to have to keep a strapwrench in my bag for my old Evil kit when the front would unscrew from the back. You get 3 different lengths and 5 backs so you can shoot any paint accurately. If you have a Cocker, definitely buy it.