mini-hakkero
A small octogonal box with magical symbols (bagua) engraved on it, carried by Kirisame Marisa of Touhou fame. It's primarily used to unleash her infamous Master Spark spell card attack, and was crafted by Morichika Rinnosuke.
The original 八卦炉 (Japanese pronunciation:hakkero) appeared in Journey to the West for the first time.