This barrel kit has extreme tolerance (12.7mm/.5inch bore) to increase the output of the HDP50 to 20 Joules when combined together with the power kit. The barrel kit comes in 2 parts, the barrel with a thread protector.
The final power output is depending on the type of air and ammo used.
Made in Germany
NOTE: By installing this barrel to your HDP, your factory warranty on your HDP will be voided.