*[[C4CPC]] Cartridge replacement for the Amstrad Plus range and the GX4000
*[https://overange.weebly.com/amstrad-gx4000-cpc-464-6128-plus-reflashable-flash-cartridge.html Flash+ cartridge] Amstrad CPC+ GX4000 reflashable cartridge
*[https://store.backbit.io/product/backbit-pro/ Backbit BackBit Pro] [https://youtu.be/tI2wkelVzyw?si=4GCoHa7wLvsFHAAR Tutorial] Universal instant loading cartridge
*[[M4 Board]] Supports CPR cartridges, among many other features