a high speed frog including a ductile iron main pan casting having an integral straight approach runner , an integral straight exit runner , and an integral exit turnout runner , a movable runner having a pair of guide rails , an electric solenoid for rotating the movable runner so that one of said pair of guide rails is cooperatively associated with the stationary runner , diverts a sliding contact shoe to the turn - out runner , a mechanical deflector engageable for resetting the movable runner so that the other of the pair of guide rails engages the integral straight approach runner , and a renewable runner insert disposed between integral straight approach runner and the respective guide rails of the movable runner .