advanceleftskip-3pt advancerightskip-3pt A parallelotope $P$ is called textit{free} along a line $l$ of the ambient space if the Minkowski sum of $P$ with a segment of the line $l$ is a parallelotope. We prove that the Voronoi conjecture is true for a free parallelotope~$P$ along $l$ and its projection along the line $l$ if each 4-belt of $P$ has either 0 or 4 facets parallel to~$l$. looseness=-1.
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