The 6mm Badger shows his project in putting together this HPA-powered M4 GBBR with the Airtac HPA Adapter... "In this video, I take on an exciting project—building and installing an Airtac HPA adaptor for my VFC M4 gas blowback replica. This adaptor transforms your airsoft setup by allowing the use of high-capacity AEG magazines, offering a lightweight, efficient, and economical alternative to traditional gas magazines. Airtac, a UK-based company, has designed this innovative adaptor to provide superior performance and customization options for airsoft enthusiasts."