The Prometheus EG G&G Arp 556 / Arp 9 inner barrel have an inner bore width of 6.03 mm and are made of stainless steel. This provides superior strength/stiffness needed to maintain accuracy without the need for coatings. The extremely precise finish ensures great performance.

The barrel is the heart of any airsoft replica and determines several performance factors such as speed (FPS), accuracy and precision (consistency).

available in different lengths.