Jonathan Higgs goes over the Arcturus Centaur B in this Airsoftology review. This AEG from MOS Manufacture takes in AK-style AEG magazines as it uses a Version 3 gearbox with 8mm bearings. It also has CNC upper receiver and a lower receiver that has QPQ processed stamped steel.

It looks like an ACR with its profile resembling one so it could be easily mistaken for a Masada ACR.  It comes with a variable cap DMag Magazine and a 320-round AEG magazine.