This extremely accurate 14" Cocker barrel is made of PPS special .680 smooth bore brass. The inside is polished to a mirror image to reduce friction on the ball. The exterior is Nickel Plated. The Dual Spiral Venting dissipates that blast behind the ball creating a less turbulent cylinder of gas. This helps keep the ball on course and reduces the report. . Each barrel includes a .680 Sizer and a .680 insert with Wedgits. Just slide in the sizer that best match the paintballs you are using.