Buffalo from Japan has announced their new Micro USB thumb key in the RMUM Series. It measures at just 15 x 22 x 8mm and weighs 2.3grams. Apparently, it is a microSDHC card reader which sold with 1, 2, 4 or 8GB microSD Card. The RMUM is available this December in Japan. More pictures after the break.

[via Akihabaranews]