**[[Dk'tronics|dk'tronics]] memory expansion 64K-512K and compatibles ([[Dobbertin|Dobbertin]], [[SYMBiFACE II|SYMBiFACE II]])
**[[SYMBiFACE II|SYMBiFACE II]] (realtime clock; PS/2 mouse; IDE interface, Ram/Rom expansion)
**[[AMX Mouse|AMX]] and [[Kempston Mouse|Kempston mouse ]] (PCW)
**Sunrise IDE interface (MSX)
**MegaSD card interface for OCM, MegaflashRomSCC+SD (MSX)