The first release was from Acorn and came with the initial 486SX33 PC cards - then it was published in version 2, now called PCPro, by Aleph One. A later major improvement brought version 3, which is still available and supports RISC OS 4 and Kinetic machines. A range of PC cards with different processors were available, but new Risc PC cards are no longer sold. Cards for earlier machines are, however, still available from Aleph One.