Abstract. We elaborate on the use of shadow systems to prove a particular case of the conjectured lower bound of the volume product P(K) = min z∈int(K) |K|||K z |, where K ⊂ R n is a convex body and1 for all x ∈ K} is the polar body of K with respect to the center of polarity z. In particular, we show that if K ⊂ R 3 is the convex hull of two 2-dimensional convex bodies, then P(K) P(∆ 3 ), where ∆ 3 is a 3-dimensional simplex, thus confirming the 3-dimensional case of Mahler conjecture, for this class of bodies. A similar result is provided for the symmetric case, where we prove that if K ⊂ R 3 is symmetric and the convex hull of two 2-dimensional convex bodies, then P(K) P(B