  We consider $K_X$-negative extremal contractions $f\colon X\to (Z,o)$, where
$X$ is an algebraic threefold with only $\epsilon$-log terminal Q-factorial
singularities and $(Z,o)$ is a two (resp., one)-dimensional germ. The main
result is that $K_X$ is 1, 2, 3, 4 or 6-complementary or we have, so called,
exceptional case and then the singularity $(Z\in o)$ is bounded (resp., the
multiplicity of the central fiber $f^{-1}(o)$ is bounded).
