Highlander Airsoft checks another 416-style AEG from East Crane, the E&C SMR16 7" CQB Gen 4 AEG. This has the ECEC System which is what they call its quick spring change system. This AEG is also is fully compatible with LiPo 7.4V / 11.1V and LiFe 6.6V / 9.9V batteries.