A molded or extruded article, e.g., an electrical part or shielded cable, comprises at least one insulation layer and at least one semiconductive layer, the semiconductive layer thick and comprising in weight percent: A. 1 to 30 wt % of conductive filler; B. 10 to 90 wt % of a non-olefin elastomer; C. 10 to 90 wt % of an olefin elastomer; and D. Optionally, 0.5 to 2.5 wt % of peroxide. Carbon black and/or metal particulates or powder typically comprise the filler, silicone or urethane rubber the non-olefin elastomer, and EPR or EPDM the olefin elastomer.