Brand: Tombow Pencil Co.
Made in: Japan
Let's not confuse this with the typical Mono. I am almost certain these pre-date them and was most likely the original name given to the range of pencils...clearly the famed Mono 100 was the higher grade. Want one that actually says Mono 50?
This Japanese company was founded in 1913 and is still manufacturing fine writing instruments more than 100 years later.