This barrel kit includes 8 different bore sizes so you can find a good barrel/paint match no matter which kind of paint you are shooting. Paintballs very in size from band to brand - sometimes even from case to case. The big problem is when paintballs don't fit the bore size of you barrel they will not shoot sraight. Players are always asking themselves: WILL THE PAINT FIT? Never ask that question again with the Freak. Instead, ask which insert you should use. Paint varies. So Smart Parts made a system that adapted to the paintball, not the other way around. One barrel, eight bore sizes. Buy a tiny ball: we have a .679 insert. Medium ball: be happy with the .689. Buy big or just leave paint in the sun all day: we have .695. Freak inserts are subjected to the same rigorous honing and hardcoat anodizing as all Smart Parts barrels. They are held to strict tolerances to make sure your .684 is just that, not smaller or larger. The Total Freak Barrel system provides the ultimate in paintball marker barrel systems. The two piece barrel system Includes all 8 bore insert sizes: .679, .682, .684, .687, .689, .691, .693, .695 and a protective carry case to store them in. Includes Aluminum Base and your choice length of tip