Extended RAM Cartridge
From Sega Retro
I was going to ask where the English name for this came from... before realising it was me who started this page back in 2012. Whoops.
The actual name is 拡張ラムカートリッジ or "Kakuchou RAM Cartridge", so unless someone finds an official source saying otherwise, I'll probably move it to that name at some point in the near future. It's a big-ish change, hence the heads up -Black Squirrel (talk) 13:34, 18 May 2021 (EDT)