The new G&G Hop-Up Unit is made of particularly durable composite plastic material in a one-piece design. This seals the hop-up unit very well and the rotary-style metal adjustment wheel makes it easier and more precise to adjust.
The G&G hop-up system can be installed in many M4 / M16 AEG and S-AEG rifles (from different manufacturers) and noticeably improves shooting performance (compared to standard hop-up systems).