Mach Sakai tries what he says is a super lightweight M4 AEG. The X-Bone Airsoft Custom G&G FireHawk AEG weighs just 1kg and it is compact. It comes equipped with a suppressor, Tokyo Marui Pro-Sight, fiberglass handguard, and fiberglass stock. There is no mention if there are internal upgrades done. Watch him go over the feature and the usual quick steel challenge test.
Picholina appears on Peace Combat TV to talk about a custom AEG from X-Bone Airsoft. According to the description, it weighs 1,400g and it's called the FIRE HAWK Kai SHOOTER SPL High Response Dual Tune Custom AEG if it's a compact M4 AEG that you can get ideas from in building your own.