Rod

An intricately carved or shaped rod of bone, stone, metal, or more exotic materials. Such rods are used by spellcasters to focus their attention and arcane energy.

Spellcasting Focus. An arcane focus is a special item designed to channel the power of arcane spells. A sorcerer, warlock, or wizard can use such an item as a spellcasting focus, using it in place of any material component which does not list a cost.