Another video from WGC Shop on an Azimuth upgrade part for the VFC MP5 Gas Blowback, the Azimuth Recoil Rod with Buffer for Umarex / VFC MP5K GBB... "Optimized spring length to accommodate shortened receiver to reduce gas usage and increase cycle speed. It is a Stainless shaft with POM bushings for smooth cycle. The Buffer included to further increase cycle speed and shorten bolt travel. Suitable for Umarex / VFC MP5K GBB."