Cesar shows how to turn an airsoft pistol into an SMG with one of the SRU SMG Kits in this 0'20 Magazine video. The SRU kits are 3D printed conversion kits that allow you to put together an SMG or compact rifle with your airsoft pistol, depending on what model they have made one for. SRU also makes conversion kits for airsoft rifles and carbines turning them into bullpups or futuristic looking ones.