The 510 collator/feeder hybrid is available in four different configurations the C 510, the AC 510, the CF 510 and the ACF 510. The C model is limited to collation work. AC includes air separation for coated or normally difficult to handle stocks. F stands for feeder ability which means it is suited for the digital print market. All 510 models can be used in the System 50 but feeder ability is not possible as this is a system for the analogue market.