Rencong is the traditional weapon of Aceh, its shape resembles the letter L, and if you look closer its shape is Bismillah calligraphy writing. Rencong included in the category of dagger (not a knife or sword).
Rencong have tiers; for the King or Sultan usually made of ivory (sarong) and pure gold (the dagger). While other rencong rencong-usually made of buffalo horn or wood as a sheath, and brass or white metal as a dagger.