The Avalon MK18 Mod0 AEG, made by VFC which was first released over 10 years ago gets update for 2019 with the ECS Gearbox and features the Daniel Defense rail system. Airsoft Atlanta has it in stock and here is their take on this AEG... "A review of the MK18 Avalon VFC M4 AEG - with Daniel Defense rail system (licensed).  A fully licensed airsoft MK18 gun from Avalon/Elite Force with newly upgraded internal parts for 2019. This is a top of the line advanced MK18 carbine, full metal, the best parts, etc. Upgraded small mosfet unit. New Avalon ECS gearbox."