As already said.. not much to be anodised on a stock Ion. Firing can is inside plastic body and hidden. Trigger frame is cast metal and may not anodise well.. I think that's why it's painted at factory. Other than that its external parts like barrel, inline reg, feedneck or ASA. Value of the marker is low so not really worth chucking a lot of money at. Metal body kitted (BOB) Ion's give you a few more options.