Abstract: A corrugated plastic article comprising at least two corrugated plastic films each of polyethylene terephthalate held in contact with each other and capable of substantially maintaining its shape under extreme use conditions.Such corrugated plastic article when heated for 5 minutes at 150.degree.C. has a percent (%) fallout (i.e., the original peak-to-peak height of the corrugations minus the retained peak-to-peak height thereof after heating divided by the original peak-to-peak height) of less than 35%.In an electrical cable having a conductor core, this corrugated plastic article provides an improved protective member for the core, having good dielectric strength and mechanical strength, electrical stability, low moisture sensitivity and other properties, wherein the corrugations, strength and shape-retention capabilities of the article provide improved cushioning, insulation and other protection for the core.