Buck 303 Folding 3-blade pocket knife

The handle material on a vintage Buck 303 knife etched with the “Cronatron” logo is typically Saw Cut Delrin (a type of durable high-impact plastic). The dark brown color is part of the material finish, not natural wood. 

While current and other historical versions of the Buck 303 Cadet model have been made with genuine woods like ebony or granadillo, the specific Cronatron promotional knives from the early 1990s (around 1993) generally featured the plastic/synthetic handles which were common on production models at that time.