Electrical Steel Conduit, Gi Slotted Channel, Gi Trunking manufacturer / supplier in China, offering HDG 25mm Through Way Boxes Two Way Boxes Steel BS4568/En61386, Two Gang 3*6 Galv. Switch & Socket Gi Box 16mm 25mm 35mm Hight, BS4568/En61386 Malleable Iron Back Outlets Boxes One Way HDG Steel 20mm and so on.