Abstract: A portable plastic film wrapping system comprises a push-cart having a vertical mast member mounted thereon. A film roll carriage is vertically movable along the mast member, and the film roll carriage is operatively connected to a counterweight which is movably disposed within the mast member. The mast member is provided with a plurality of apertures, and a redundant dual stop pin assembly is engageable within particular ones of the mast member apertures so as to incrementally lockingly retain the film roll carriage at a particular elevations along the mast member such that safe controlled movement of the film roll carriage along the mast member is achieved.