The storage unit comprises at least two flexible members (55), equipped with supports (57) for the products to be stored, extending and moving along respective parallel paths defined by a plurality of driving wheels (59, 63). The supports (57) project laterally in respect of the relative flexible member. In each of the paths, in proximity to at least one driving wheel, a transfer member (71) is positioned to receive the products from the supports located on a branch (55A) of the respective flexible member upstream of said driving wheel and transfer them to the supports located on a branch (55B) of said flexible member downstream of said driving wheel in respect of the direction of feed of the flexible members along the respective paths, so that the products follow a trajectory that by-passes said driving wheel.