An ethylene-\u03b1-olefin copolymer wherein the copolymer has a monomer unit based on ethylene and a monomer unit based on an \u03b1-olefin having 3 to 20 carbon atoms, the density is 860 to 950 kgm3, the melt flow rate is 1 to 100 g10 min, the flow activation energy is 60 kJmol or more, the ratio of the weight average molecular weight to the number average molecular weight is 5. The device comprises an electrical socket and a pneumatic socket, both mounted on an item of equipment, an electrical plug secured to a cable, the electrical plug being intended to be connected to the electrical socket, and a pneumatic plug secured to a cable, the pneumatic plug being intended to be connected to the pneumatic socket. but not higher than a melting start point.