BY40 type surge protective device (short name "SPD") is suitable for ... installation dimension about the device like the figure.Technical Parameters : BY40-10/ -140BY40-10/ -275BY40-10/ -320BY40-10/ -385BY40-10/ -420BY40 ... PBTConnect waysL ,N2.5 --- 35 mm2Earthing4.0 --- 35mm2Signal line1.5 BY40 Series Surge Protective Devices