STL file HI-CAPA to M4 HPA ADAPTER・Design to download and 3D print・Cults
I know a lot of people hate the Primary Airsoft adapters, but when it's 110° outside, a light kit is a life saver. Also a great first step into HPA : r/airsoft
TAPP Airsoft Tapp M4 Adapter for Hi-Capa | Modular Series
Primary Airsoft - HI-CAPA WE TECH HPA/M4 ADAPTER - AirsoftJunkiez.com