A vending machine is provided with an internal product holding assembly where product to be vended is held or stacked within each of a plurality of product holding compartments formed by a plurality of spaced apart stacking walls. Compartment depth is variable, so as to dispense varying length products, by a movable rear wall movably mounted to one side of a stacking wall so as to be incrementally adjustable within the compartment between a plurality of selected fore and aft positions. The stacking walls have a hollow interior housing an adjusting mechanism for incrementally moving the depth controlling rear wall, with the adjusting mechanism being operable from the front of the product holding assembly and retainable at a selected position.