... SGS,BSI,ISO,ITS,BV certificates 3. Suppliers for the Burj Dubai Conduit fittings-Conduit accessories 1 ... Tapped M4 at 50.3mm centres.Large81mm internal diameter, for conduits of 20 & 25mm dia = 35mm and 32mm ... are available with tapped hole in the base for earthing screw. Covers and fixing screws need ... 10x20' Container Angle with Back Outlet Box - Metallic Electric Conduit & Fittings According to BS4568