An oil-based colored pencil with wrapped paper encasing by Mitsubishi. Set of 12.

The crayon-like grease pencil can be applied onto non-porous surfaces, and be wiped down with a cloth. Known to be the IT pencil to accompany photo negatives, these versatile pencils can write on plastic, glass, metal, ceramic, vinyl etc. The colors appear vibrant on dark surfaces, porous or not. 

The soft colored pencil is easy to draw with, and blends well with other colors. Ecological since you can use the whole stick without breakage and getting your hands dirty. Simply pull on the string to peel off the paper encasing to expose the inner core.