!!Important information from the VFC Service Center!!
The BCM-AIR QD receiver end plate for the MCMR AEG version only accepts compact/short tip style QD swivels, because there are gearbox and power wires inside the rear of AEG receiver. Also, the rear end of AEG receivers are opened, so the QD port must be closed bottom to prevent dusts or splashes goes into the rifle accidentally.
The part number of compact MCMR AEG QD swivel is V020SP1010, if need one please contact local VFC dealer or mail to VFC official service mailbox: firstname.lastname@example.org