Mach Sakai reviews the SR-25K AEG made by A&K Airsoft. This AEG has been in production for over a decade now and depending on your location, it may or many not have the KAC markings, such as the early production units. This is a full metal AEG with a custom Version 2 gearbox and has a full length RIS rail. It can be fired in semi and full auto modes.