Radite is a trade name for an early plastic, formed of pyroxylin -- a partially nitrated cellulose -- manufactured by DuPont and introduced by the Sheaffer Pen Company in 1924 when plastics were first used as a material for pen manufacture.

Sheaffer's Radite pens were the first commercial plastic pens,^[1] and Sheaffer marketed the material as "indestructible."^[2] Jade green in color, the pens were best sellers at the time.^[3] The material is credited with helping Sheaffer capture 25% of the market.^[4]

Radite is extremely similar to other celluloid pen materials trademarked at the time, such as Permanite, Pyralin, Fiberloid, Viscoloid, and Herculoid.^[1]