The program provided a small number of RSXs which selected formats for each drive, simply by copying values into the [[XDPB]].
As with [[S-DOS]] and [[400K/S]], this meant that double-sided formats were not supported, so the user needed a [[side switchSide Select Switch]] to use each disc to its full capacity.
One unusual design feature, which had both advantages and disadvantages, was the presence of a "boot loader"-type program on certain formats.