railbars of a switch which are used to maintain the gauge between movable railbars two parts 10 and 12 are connected to each other by two t shaped insulating joints or switch plates 16 having t shaped cross sections each insulating joint 16 includes a metallic core encased with an electrically insulating material each core is t shaped with a flat body 17 a having a leg or ridge 17 b depending therefrom likewise the insulating joint 16 includes a flat body 17 c and a depending leg 17 d the depending leg 17 d is received within a gap g defined between the first part 10 and the second part 12 ends of the depending legs 17 d abut against each other alternatively it is believed that the metallic core can be a flat plate encased with an electrically insulating material replacing the depending leg or ridge 17 b completely with insulating material as shown in fig8 alternatively the insulating joints can be flat as opposed to t shaped and an electric insulative filling can be provided between the insulating joints in the gap g defined by the opposed ends of the first part 10 and the second part 12 for electrically insulating these two parts 10 and 12 from each other the insulating joints 16 are secured to the first part 10 and the second part 12 by a fastening arrangement of bolts 20 nuts 22 and washers 24 more specifically the insulating joint 16 includes a steel core 26 with a plurality of holes defined therein through which bolts 20 extend an insulating layer 28 encasing the steel core 26 and a plurality of bushings 30 provided in the holes fig2 shows the bushings 30 which are.