HPA Adapter for Hi-Capas
Feeds from MP5/SMG-5 AEG magazines
US-Spec HPA Line connector 
If you plan to run your Hi-Capa GBB pistol with high pressure air, the Novritsch HPA SMG-5 Magazine Adapter for Hi-Capa GBB Pistols is essential. This magazine adapter allows your Hi-Capa GBB to feed from curved MP5/SMG-5 AEG mid-cap magazines and HPA from an external tank (not included), increasing capacity considerably and practically eliminating FPS fluctuation due to the "cooldown" effect. 
The adapter is pre-assembled, meaning you don't need to mess around putting it together or run the risk of doing it wrong and causing injury. Naturally, you'll need an HPA bottle, air line and regulator to use this adapter and the fitting is US Spec, meaning only US Spec air lines will fit. If you want to eliminate cooldown, improve rapid-fire performance and increase your mag capacity, the Novritsch HPA SMG-5 Magazine Adapter for Hi-Capa GBB Pistols is what you need!