A trademarked name for thin-walled body tubing made from phenolic impregnated paper and used with model rockets built for competition, especially superrocs. It was prized by some competition rocket flyers because it was stronger than ordinary cardboard tubing, but lighter than fiberglass. Blackshaft tubing - so called because it was black in color - was sold by Apogee Components. In some circles it earned the derogatory name "blackshatter" due to its inability to absorb any lateral shock without breaking. Manufacture of blackshaft tubing was discontinued in 1994.